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Muonic atom spectroscopy with microgram target material. Adamczak, A.; Antognini, A.; Berger, N.; Cocolios, T. E.; Deokar, N.; Düllmann, Ch. E.; Eggenberger, A.; Eichler, R.; Heines, M.; Hess, H.; Indelicato, P.; Kirch, K.; Knecht, A.; Krauth, J. J.; Nuber, J.; Ouf, A.; Papa, A.; Pohl, R.; Rapisarda, E.; Reiter, P.; Ritjoho, N.; Roccia, S.; Seidlitz, M.; Severijns, N.; von Schoeler, K.; Skawran, A.; Vogiatzi, S. M.; Warr, N.; Wauters, F. in The European Physical Journal A (2023). 59(2)
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Lifetime measurement of excited states in 116Xe. Lakenbrink, Casper-David; Beckers, Marcel; Blazhev, Andrey; Dewald, Alfred; Dunkel, Felix; Esmaylzadeh, Arwin; Fransen, Christoph; Jolie, Jan; Knafla, Lukas; Müller-Gatermann, Claus; von Spee, Franziskus; Zell, Karl-Oskar in The European Physical Journal A (2023). 59(12) 290.
Lifetimes of excited states in 116Xe were measured using the recoil-distance Doppler-shift technique. Excited 116Xe nuclei were populated in the fusion-evaporation reaction 102Pd(16O,2n)116Xe. Lifetimes of the 2+_1 and 4+_1 states were evaluated using the differential decay-curve method with gamma gamma -coincidence data as well as lifetimes of the 6+_1 and 7-_1 states using simulations of spectra considering Doppler-shift attenuation effects.
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Agata detector technology: recent progress and future developments. Eberth, J.; Hess, H.; Reiter, P.; Bertoldo, S.; Carraro, C.; Maggioni, G.; Napoli, D. R.; Raniero, W.; De Salvador, D. in The European Physical Journal A (2023). 59(8) 179.
{\\($}{\$\)}{backslash}gamma {\\($}{\$\)}-ray tracking is based on a new generation of position sensitive high-purity germanium (HPGe) detectors. A novel type of cluster detector was successfully developed and assembled for the high-resolution {\\($}{\$\)}{backslash}gamma {\\($}{\$\)}-ray spectrometer Advanced Gamma Tracking Array AGATA. The core part of the detector consists of three encapsulated, 36-fold segmented HPGe detectors which are operated in a common cryostat. The Ge crystal is hermetically sealed inside an aluminium can. All energy channels provide best energy resolution of core and segment signals for an extended energy range well above 50 MeV. A low cross-talk level was determined for the HPGe detectors and its preamplifier circuitry. Related cross-talk corrections are essential for highest energy resolution and improved position dependent pulse shape information. Recently a new encapsulation technology was put into operation which is based on a renewable metal elastic seal. HPGe detector developments are concerned with technologies for the production of p+ and n+ contacts, the segmentation and passivation of encapsulated HPGe crystals. Semiconductor processing research specifically aimed to develop a stable, thin and easy to segment n+ contact. A novel process, based on pulsed laser melting PLM, was successfully employed to produce very thin n+ and p+ contacts preserving the Ge purity. The contacts were segmented using a photolithographic process and then the intrinsic surface between contacts was passivated to assure the electrical insulation between them. A small detector prototype with three segments was made using these new techniques and then successfully tested.
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Coulomb excitation of 74,76Zn. Illana, A.; Zielińska, M.; Huyse, M.; Rapisarda, E.; Van Duppen, P.; Wrzosek-Lipska, K.; Lenzi, S. M.; Nowacki, F.; Dao, D. D.; Otsuka, T.; Tsunoda, Y.; Arnswald, K.; Borge, M. J. G.; Cederkäll, J.; Chrysalidis, K.; Cortès, M. L.; Cox, D. M.; Day Goodacre, T.; De Witte, H.; Doherty, D. T.; Fedosseev, V.; Gaffney, L. P.; Hadyńska-Klẹk, K.; Hess, H.; Henrich, C.; Hlebowicz, M.; Komorowska, M.; Korten, W.; Kröll, Th.; Lozano Benito, M. L.; Lutter, R.; Marsh, B.; Martikainen, L.; Matejska-Minda, M.; Molkanov, P. L.; Nacher, E.; Nannini, A.; Napiorkowski, P. J.; Pakarinen, J.; Papadakis, P.; Queiser, M.; Reiter, P.; Rocchini, M.; Rodriguez, J. A.; Rolke, T.; Rosiak, D.; Rothe, S.; Seidlitz, M.; Seiffert, C.; Siebeck, B.; Siesling, E.; Snäll, J.; Srebrny, J.; Thiel, S.; Warr, N.; Wenander, F. in Phys. Rev. C (2023). 108(4) 044305.
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Conceptual design of the AGATA 2π array at LNL. Valiente-Dobón, J.J.; Menegazzo, R.; Goasduff, A.; Agguiaro, D.; Aguilera, P.; Angelini, F.; Balogh, M.; Bazzacco, D.; Benito, J.; Benzoni, G.; Bez, N.; Bolognesi, M.; Bottoni, S.; Brugnara, D.; Carollo, S.; Cocconi, P.; Cogo, A.; Collado, J.; Crespi, F.C.L.; Ertoprak, A.; Escudeiro, R.; Galtarossa, F.; Gamba, E.R.; Gambalonga, A.; Servín, B. Góngora; Gottardo, A.; Gozzelino, A.; Gulmini, M.; Huang, Z.; Marchi, T.; Mengoni, D.; Modanese, P.; Napoli, D.R.; Pellumaj, J.; Pérez-Vidal, R.M.; Pigliapoco, S.; Pilotto, E.; Ramina, L.; Rampazzo, M.; Raniero, W.; Rebeschini, M.; Rezynkina, K.; Rosso, D.; Scarcioffolo, M.; Scarpa, D.; Sedlák, M.; Smith, R.; Toniolo, N.; Veronese, F.; Volpe, V.; Zago, L.; Zanon, I.; Zhang, G.; Abels, R.; Allegrini, M.L.; Aufranc, C.; Baulieu, G.; Belkhiria, C.; Benettoni, M.; Benini, D.; Bentley, M.; Biasotto, M.; Blaizot, M.; Miquel, J. Blasco; Boiano, C.; Boston, A.; Boston, H.; Boujrad, A.; Bourgault, P.; Bracco, A.; Brambilla, S.; Burrows, I.; Camera, F.; Capra, S.; Capsoni, A.; Cash, R.; Civera, J.V.; Clément, E.; Coelli, S.; Cordwell, M.; Corradi, L.; Coudert, S.; De Angelis, G.; De Ruvo, L.; Debras, G.; Del Fabbro, M.; Diklić, J.; Dosme, N.; Duchene, G.; Duclos, B.; Dudouet, J.; Eberth, J.; Elloumi, S.; Everett, C.; Fantinel, S.; Fillinger, M.; Fioretto, E.; Fransen, C.; Gadea, A.; Gibelin, L.; González, V.; Goupil, J.; Görgen, C.; Grant, A.; Green, K.; Ha, J.; Hartnett, T.; Henseler, K.; Hess, H.; Hirsch, R.; Houarner, C.; Jacob, J.; Joannem, T.; Judson, D.S.; Karkour, N.; Karolak, M.; Kebbiri, M.; Kieffer, J.; Labiche, M.; Lafay, X.; Le Jeannic, P.; Lefevre, A.; Legay, E.; Legruel, F.; Lenzi, S.; Leoni, S.; Linget, D.; Liptrot, M.; López-Martens, A.; Lotodé, A.; Manara, L.; Ménager, L.; Mijatović, T.; Million, B.; Minarello, A.; Montagnoli, G.; Morrall, P.; Mullacrane, I.; Nyberg, J.; Philippon, G.; Polettini, M.; Popieul, F.; Pullia, A.; Recchia, F.; Reiter, P.; Richardt, G.; Rocchini, M.; Roger, A.; Saillant, F.; Sanchis, E.; Laskar, Md.S.R.; Secci, G.; Sigward, M.-H.; Simpson, J.; Solenne, N.; Spee, F.; Stefanini, A.M.; Stézowski, O.; Szilner, S.; Templeton, N.; Theisen, Ch.; Thiel, S.; Tomasi, F.; Tzvetkov, S.; Vigano, D.; Viscione, E.; Wieland, O.; Wimmer, K.; Wittwer, G.; Zielińska, M. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2023). 1049 168040.
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High-Precision Spectroscopy of 20O Benchmarking Ab Initio Calculations in Light Nuclei. Zanon, I.; Clément, E.; Goasduff, A.; Menéndez, J.; Miyagi, T.; Assié, M.; Ciema\l{}a, M.; Flavigny, F.; Lemasson, A.; Matta, A.; Ramos, D.; Rejmund, M.; Achouri, L.; Ackermann, D.; Barrientos, D.; Beaumel, D.; Benzoni, G.; Boston, A. J.; Boston, H. C.; Bottoni, S.; Bracco, A.; Brugnara, D.; de France, G.; de Sereville, N.; Delaunay, F.; Desesquelles, P.; Didierjean, F.; Domingo-Prato, C.; Dudouet, J.; Eberth, J.; Fernández, D.; Fougères, C.; Gadea, A.; Galtarossa, F.; Girard-Alcindor, V.; Gonzales, V.; Gottardo, A.; Hammache, F.; Harkness-Brennan, L. J.; Hess, H.; Judson, D. S.; Jungclaus, A.; Kaifmmode \mbox{\c{s}}else \c{s}\fi{}kaifmmode \mbox{\c{s}}else \c{s}\fi{}, A.; Kim, Y. H.; Kuifmmode \mbox{\c{s}}else \c{s}\fi{}oifmmode \breve{g}else \u{g}\fi{}lu, A.; Labiche, M.; Leblond, S.; Lenain, C.; Lenzi, S. M.; Leoni, S.; Li, H.; Ljungvall, J.; Lois-Fuentes, J.; Lopez-Martens, A.; Maj, A.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Million, B.; Napoli, D. R.; Nyberg, J.; Pasqualato, G.; Podolyak, Zs.; Pullia, A.; Quintana, B.; Recchia, F.; Regueira-Castro, D.; Reiter, P.; Rezynkina, K.; Rojo, J. S.; Salsac, M. D.; Sanchis, E.; ifmmode \mbox{\c{S}}else \c{S}\fi{}enyiifmmode \breve{g}else \u{g}\fi{}it, M.; Siciliano, M.; Sohler, D.; Stezowski, O.; Theisen, Ch.; Utepov, A.; Valiente-Dobón, J. J.; Verney, D.; Zielinska, M. in Phys. Rev. Lett. (2023). 131(26) 262501.
The excited states of unstable \($^{20}\mathrm{O}$\) were investigated via \($\ensuremath{\gamma}$\)-ray spectroscopy following the \($^{19}\mathrm{O}(d,p)^{20}\mathrm{O}$\) reaction at \($8\text{ }\text{ }A\mathrm{MeV}$\). By exploiting the Doppler shift attenuation method, the lifetimes of the \(${2}_{2}^{+}$\) and \(${3}_{1}^{+}$\) states were firmly established. From the \($\ensuremath{\gamma}$\)-ray branching and \($E2/M1$\) mixing ratios for transitions deexciting the \(${2}_{2}^{+}$\) and \(${3}_{1}^{+}$\) states, the \($B(E2)$\) and \($B(M1)$\) were determined. Various chiral effective field theory Hamiltonians, describing the nuclear properties beyond ground states, along with a standard USDB interaction, were compared with the experimentally obtained data. Such a comparison for a large set of \($\ensuremath{\gamma}$\)-ray transition probabilities with the valence space in medium similarity renormalization group ab initio calculations was performed for the first time in a nucleus far from stability. It was shown that the ab initio approaches using chiral effective field theory forces are challenged by detailed high-precision spectroscopic properties of nuclei. The reduced transition probabilities were found to be a very constraining test of the performance of the ab initio models.
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Examination of how properties of a fissioning system impact isomeric yield ratios of the fragments. Gjestvang, D.; Wilson, J. N.; Al-Adili, A.; Siem, S.; Gao, Z.; Randrup, J.; Thisse, D.; Lebois, M.; Jovancević, N.; Canavan, R.; Rudigier, M.; Étasse, D.; Gerst, R.-B.; Adamska, E.; Adsley, P.; Algora, A.; Belvedere, C.; Benito, J.; Benzoni, G.; Blazhev, A.; Boso, A.; Bottoni, S.; Bunce, M.; Chakma, R.; Cieplicka-Oryńczak, N.; Courtin, S.; Cortés, M. L.; Davies, P.; Delafosse, C.; Fallot, M.; Fornal, B.; Fraile, L.; Gottardo, A.; Guadilla, V.; Häfner, G.; Hauschild, K.; Heine, M.; Henrich, C.; Homm, I.; Ibrahim, F.; Iskra, Ł. W.; Ivanov, P.; Jazrawi, S.; Korgul, A.; Koseoglou, P.; Kröll, T.; Kurtukian-Nieto, T.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Lozeva, R.; Matea, I.; Miernik, K.; Nemer, J.; Oberstedt, S.; Paulsen, W.; Piersa-Siłkowska, M.; Popovitch, Y.; Porzio, C.; Qi, L.; Regan, P. H.; Rezynkina, K.; Sánchez-Tembleque, V.; Schmitt, C.; Söderström, P.-A.; Sürder, C.; Tocabens, G.; Vedia, V.; Verney, D.; Warr, N.; Wasilewska, B.; Wiederhold, J.; Yavahchova, M.; Ziliani, S. in Phys. Rev. C (2023). 108(6) 064602.
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Agata characterisation and pulse shape analysis. Boston, A. J.; Crespi, F. C. L.; Duch{ê}ne, G.; D{é}sesquelles, P.; Gerl, J.; Holloway, F.; Judson, D. S.; Korichi, A.; Harkness-Brennan, L.; Ljungvall, J.; Quintana-Arn{é}s, B.; Reiter, P.; Stezowski, O. in The European Physical Journal A (2023). 59(9) 213.
The AGATA and GRETA spectrometers are large arrays of highly segmented HPGe detectors that use the technique of gamma ray tracking to reconstruct the scattering path of gamma rays interacting within the active material. A basic requirement is a precise reconstruction of the individual interaction locations within the detectors. This is possible through the use of pulse shape analysis which has to be conducted in real time due to the high data rates generated by the spectrometer. The methodologies that have been evaluated to perform this for AGATA are discussed along with the approaches used to calculate the pulse shape databases required by these algorithms. Finally, the performance and limitations of the existing approaches are reviewed.
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Lifetime measurements in 96Rb via fast-timing techniques: Investigating shape coexistence at A≃100. Gamba, E. R.; Bottoni, S.; Iskra, Ł. W.; Zavaglia, C.; Leoni, S.; Fornal, B.; Cieplicka-Oryńczak, N.; Benzoni, G.; Colombi, G.; Crespi, F. C. L.; Esmaylzadeh, A.; Jentschel, M.; Jolie, J.; Karayonchev, V.; Kim, Y. H.; Knafla, L.; Köster, U.; Ley, M.; Mǎrginean, N.; Mǎrginean, R.; Michelagnoli, C.; Polettini, M.; Porzio, C.; Régis, J-.M.; Reygadas, D.; Turturica, A. in Phys. Rev. C (2023). 108(6) 064301.
Lifetime measurements of the 3-, 4-, and 6- intraband states in the neutron-rich, odd-odd 96Rb nucleus were performed at the LOHENGRIN spectrometer of Institut Laue-Langevin, using thermal-neutron-induced fission of 235U and fast-timing techniques with LaBr3(Ce) scintillator detectors. The nanosecond isomeric nature of the (3-) bandhead was established as well as the β2=0.39(3) deformation parameter of the band, pointing to a robust deformation in 96Rb. Moreover, a hindered B(E2) value of 3.9_-13^+19×(10-2) W.u. was found for the γ decay of the deformed 4- state to the spherical 2- ground state. A retardation was also found for the 3- → 2- transition, possibly due to the shape change and giving strong support to a shape coexistence scenario in this nucleus, at the borders of the island of deformation at N=60. Analogies with the structure of the 98Y isotone are discussed.
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Lifetime measurements in 92Mo: Investigation of seniority conservation in the N=50 isotones. Ley, M.; Knafla, L.; Jolie, J.; Esmaylzadeh, A.; Harter, A.; Blazhev, A.; Fransen, C.; Pfeil, A.; Régis, J.-M.; Van Isacker, P. in Phys. Rev. C (2023). 108(6) 064313.
Excited states in the yrast and negative parity bands in 92Mo were populated in two different experiments using the 90Zr(α,2n)92Mo and 93Nb(p,2n)92Mo fusion-evaporation reactions at the Cologne FN Tandem accelerator and measured using a hybrid setup of high purity germanium and lanthanum bromide detectors. Lifetimes of the excited {2}_{1}^{+}, {4}_{1}^{+}, {6}_{1}^{+}, {8}_{1}^{+}, {5}_{1}^{-}, {7}_{1}^{-} and {9}_{1}^{-} states were measured using the γ-γ fast-timing technique. The newly measured lifetime of the {4}_{1}^{+} state differs from the recently published value measured using the recoil distance Doppler shift method. Experimental B(E2) strengths of excited states in 92Mo are used to predict theoretical B(E2) values in the N=50 isotones from 93Tc up to 95Rhusing semiempirical calculations in the single-j orbital 0{g}_{9/2} for the protons.
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Shape polarization in the tin isotopes near N = 60 from precision g-factor measurements on short-lived 11/2− isomers. Gray, T.J.; Stuchbery, A.E.; Dobaczewski, J.; Blazhev, A.; Alshammari, H.A.; Bignell, L.J.; Bonnard, J.; Coombes, B.J.; Dowie, J.T.H.; Gerathy, M.S.M.; Kibédi, T.; Lane, G.J.; McCormick, B.P.; Mitchell, A.J.; Nicholls, C.; Pope, J.G.; Reinhard, P.-G.; Spinks, N.J.; Zhong, Y. in Physics Letters B (2023). 847 138268.
The g factors of 11/2− isomers in semimagic 109Sn and 111Sn (isomeric lifetimes τ=2.9(3) ns and τ=14.4(7) ns, respectively) were measured by an extension of the Time Differential Perturbed Angular Distribution technique, which uses LaBr3 detectors and the hyperfine fields of a gadolinium host to achieve precise measurements in a new regime of short-lived isomers. The results, g(11/2−;109Sn)=−0.186(8) and g(11/2−;111Sn)=−0.214(4), are significantly lower in magnitude than those of the 11/2− isomers in the heavier isotopes and depart from the value expected for a near pure neutron h11/2 configuration. Broken-symmetry density functional theory calculations applied to the sequence of 11/2− states reproduce the magnitude and location of this deviation. The g(11/2−) values are affected by shape core polarization; the odd 0h11/2 neutron couples to Jπ=2+,4+,6+... configurations in the weakly-deformed effective core, causing a decrease in the g-factor magnitudes.
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Exotic decay of 115Cs. Das, P.; Datta, Ushasi; Chakraborty, S.; Rahaman, A.; Tengblad, O.; Agrawal, B. K.; Becerril, A.; Cederkall, J.; Dey, J.; Gottberg, A.; Imam, Sk Md Adil; Kowalska, M.; Kurcewicz, J.; Lund, M.; Mandal, S.; Madurga, M.; Marginean, N.; Marginean, R.; Mihai, C.; Marroquin, I.; Nacher, E.; Negret, A.; Pascu, S.; Perea, A.; Rapisarda, E.; Rotaru, F.; Ray, J.; Sharma, P.; Stora, T.; Sotty, C.; Vedia, V.; Warr, N.; Wadsworth, R. in Phys. Rev. C (2023). 108(6) 064304.
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Lifetime measurements of excited states in 57Mn. Kleis, H.; Arnswald, K.; Blazhev, A.; Droste, M.; Reiter, P.; Abels, R.; Burggraf, R.; Esmaylzadeh, A.; Fransen, C.; Hirsch, R.; Karayonchev, V.; Luyken, D.; Wehlitz, J.; Werner, D. in Phys. Rev. C (2023). 108(6) 064308.
Excited states in \($^{57}\mathrm{Mn}$\) are populated using the \($^{55}\mathrm{Mn}(^{18}\mathrm{O}$\), \($^{16}\mathrm{O})^{57}\mathrm{Mn}$\) two-neutron transfer reaction at the FN tandem accelerator in Cologne. Lifetimes of excited nuclear states in \($^{57}\mathrm{Mn}$\) were determined utilizing the Doppler-shift attenuation method. A comparison between experiment and shell-model theory was made for excitation energies and reduced transition strengths along the odd-\($Z$\) isotopes Sc, V, Mn, and Co. The new results on transition strengths in \($^{57}\mathrm{Mn}$\) are described well by the standard interactions GXPF1A and KB3G. The development along the \($N=32$\) isotones for these odd-\($Z$\) nuclei and discrepancies between experiment and theory are discussed.
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Response of the FAst TIMing Array (FATIMA) for DESPEC at FAIR Phase-0. Chishti, M.M.R.; Jazrawi, S.; Shearman, R.; Regan, P.H.; Podolyák, Zs.; Collins, S.M.; Górska, M.; Cederwall, B.; Yaneva, A.; Zhang, G.X.; Cederkall, J.; Goasduff, A.; Albers, H.M.; Alhomaidhi, S.; Banerjee, A.; Bruce, A.M.; Benzoni, G.; Das, B.; Davinson, T.; Fraile, L.M.; Gerl, J.; Häfner, G.; Jolie, J.; Hubbard, N.; John, P.R.; Lozeva, R.; Mistry, A.K.; Singh, B.S. Nara; Mikolajczuk, M.; Polettini, M.; Pietralla, N.; Regis, J.M.; Rudigier, M.; Sahin, E.; Sharma, A.; Si, M.; Vesic, J.; Werner, V. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2023). 1056 168597.
The Monte-Carlo simulated response for γ-ray detection of the FAst TIMing Array (FATIMA) for exploitation within the DEcay SPECtroscopy (DESPEC) experimental system at the FAIR Phase-0 facility at Darmstadt, Germany is presented. In this configuration, FATIMA consisted of 36 LaBr3(Ce) detectors surrounding the AIDA, position-sensitive charged-particle active stopper. The decay of the Iπ=8+ isomer-fed decay cascade in 96Pd, measured in the first DESPEC experiment at the FAIR-0 facility was used to validate the simulations. The experimental data yielded in-situ full-energy peak efficiency values for FATIMA of 11.2(11)%, 6.8(7)%, 3.8(4)% and 2.1(4)% at 106, 325, 684 and 1415 keV respectively, consistent with the values derived from the simulated response.
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Lifetime measurements in 206Po with a shell-model interpretation. Karayonchev, V.; Jolie, J.; Bittner, D.; Beckers, M.; Esmaylzadeh, A.; Fischer, J.; Fransen, C.; Garbe, J.; Knafla, L.; Lakenbrink, C.-D.; Ley, M. in Phys. Rev. C (2023). 108(5) 054302.
The lifetimes of the first excited 2+ and 4+ states in 206Po were measured using the recoil-distance Doppler-shift method. The experimental results were compared to large-scale shell-model calculations that describe the deduced transition probabilities well. Those calculations were extended to the neighboring 204,208Po isotopes giving a good overall description of the yrast states. However, the calculations underpredict the energies of the 6_1+ and 8_1+ states, which suggests that further improvement of the proton-neutron interaction is required.
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Shape evolution in even-mass 98-104Zr isotopes via lifetime measurements using the gamma-gamma-coincidence technique. Pasqualato, G.; Ansari, S.; Heines, J. S.; Modamio, V.; Görgen, A.; Korten, W.; Ljungvall, J.; Clément, E.; Dudouet, J.; Lemasson, A.; Rodríguez, T. R.; Allmond, J. M.; Arici, T.; Beckmann, K. S.; Bruce, A. M.; Doherty, D.; Esmaylzadeh, A.; Gamba, E. R.; Gerhard, L.; Gerl, J.; Georgiev, G.; Ivanova, D. P.; Jolie, J.; Kim, Y.-H.; Knafla, L.; Korichi, A.; Koseoglou, P.; Labiche, M.; Lalkovski, S.; Lauritsen, T.; Li, H.-J.; Pedersen, L. G.; Pietri, S.; Ralet, D.; Regis, J. M.; Rudigier, M.; Saha, S.; Sahin, E.; Siem, S.; Singh, P.; Söderström, P.-A.; Theisen, C.; Tornyi, T.; Vandebrouck, M.; Witt, W.; Zielińska, M.; Barrientos, D.; Bednarczyk, P.; Benzoni, G.; Boston, A. J.; Boston, H. C.; Bracco, A.; Cederwall, B.; Ciemała, M.; de France, G.; Domingo-Pardo, C.; Eberth, J.; Gadea, A.; González, V.; Gottardo, A.; Harkness-Brennan, L. J.; Hess, H.; Judson, D. S.; Jungclaus, A.; Lenzi, S. M.; Leoni, S.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Napoli, D. R.; Nyberg, J.; Podolyák, Zs.; Pullia, A.; Recchia, F.; Reiter, P.; Rezynkina, K.; Salsac, M. D.; Sanchis, E.; Şenyiğit, M.; Siciliano, M.; Simpson, J.; Sohler, D.; Stezowski, O.; Valiente-Dobón, J. J.; Verney, D. in The European Physical Journal A (2023). 59(11) 276.
The Zirconium (Z = 40) isotopic chain has attracted interest for more than four decades. The abrupt lowering of the energy of the first 2+ state and the increase in the transition strength B(E2; 2^+1, 0^+1) going from 98Zr to 100Zr has been the first example of ``quantum phase transition'' in nuclear shapes, which has few equivalents in the nuclear chart. Although a multitude of experiments have been performed to measure nuclear properties related to nuclear shapes and collectivity in the region, none of the measured lifetimes were obtained using the Recoil Distance Doppler Shift method in the gamma gamma -coincidence mode where a gate on the direct feeding transition of the state of interest allows a strict control of systematical errors. This work reports the results of lifetime measurements for the first yrast excited states in 98-104Zr carried out to extract reduced transition probabilities. The new lifetime values in gamma gamma -coincidence and gamma -single mode are compared with the results of former experiments. Recent predictions of the Interacting Boson Model with Configuration Mixing, the Symmetry Conserving Configuration Mixing model based on the Hartree--Fock--Bogoliubov approach and the Monte Carlo Shell Model are presented and compared with the experimental data.
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Search for 22Na in novae supported by a novel method for measuring femtosecond nuclear lifetimes. Foug{è}res, Chlo{é}; de Oliveira Santos, Fran{\c{c}}ois; Jos{é}, Jordi; Michelagnoli, Caterina; Cl{é}ment, Emmanuel; Kim, Yung Hee; Lemasson, Antoine; Guimar{{~a}}es, Valdir; Barrientos, Diego; Bemmerer, Daniel; Benzoni, Giovanna; Boston, Andrew J.; B{ö}ttger, Roman; Boulay, Florent; Bracco, Angela; {\v{C}}elikovi{{{'c}}}, Igor; Cederwall, Bo; Ciemala, Micha{l}; Delafosse, Cl{é}ment; Domingo-Pardo, C{é}sar; Dudouet, J{é}r{é}mie; Eberth, J{ü}rgen; F{ü}l{ö}p, Zsolt; Gonz{á}lez, Vicente; Gottardo, Andrea; Goupil, Johan; Hess, Herbert; Jungclaus, Andrea; Ka{\c{s}}ka{\c{s}}, Ay{\c{s}}e; Korichi, Amel; Lenzi, Silvia M.; Leoni, Silvia; Li, Hongjie; Ljungvall, Joa; Lopez-Martens, Araceli; Menegazzo, Roberto; Mengoni, Daniele; Million, Benedicte; Mr{á}zek, Jarom{í}r; Napoli, Daniel R.; Navin, Alahari; Nyberg, Johan; Podoly{á}k, Zsolt; Pullia, Alberto; Quintana, Bego{\~{n}}a; Ralet, Damien; Redon, Nadine; Reiter, Peter; Rezynkina, Kseniia; Saillant, Fr{é}d{é}ric; Salsac, Marie-Delphine; S{á}nchez-Ben{í}tez, Angel M.; Sanchis, Enrique; {\c{S}}enyi{\u{g}}it, Menek{\c{s}}e; Siciliano, Marco; Smirnova, Nadezda A.; Sohler, Dorottya; Stanoiu, Mihai; Theisen, Christophe; Valiente-Dob{ó}n, Jose J.; Uji{{{'c}}}, Predrag; Zieli{{{'n}}}ska, Magdalena in Nature Communications (2023). 14(1) 4536.
Classical novae are thermonuclear explosions in stellar binary systems, and important sources of 26Al and 22Na. While \($\gamma$\) rays from the decay of the former radioisotope have been observed throughout the Galaxy, 22Na remains untraceable. Its half-life (2.6 yr) would allow the observation of its 1.275 MeV \($\gamma$\)-ray line from a cosmic source. However, the prediction of such an observation requires good knowledge of its nucleosynthesis. The 22Na(p,{\thinspace}\($\gamma$\))23Mg reaction remains the only source of large uncertainty about the amount of 22Na ejected. Its rate is dominated by a single resonance on the short-lived state at 7785.0(7) keV in 23Mg. Here, we propose a combined analysis of particle-particle correlations and velocity-difference profiles to measure femtosecond nuclear lifetimes. The application of this method to the study of the 23Mg states, places strong limits on the amount of 22Na produced in novae and constrains its detectability with future space-borne observatories.
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Lifetime measurements in 99Nb and 99Zr: Investigation of shape coexistence. Pfeil, A.; Nomura, K.; Gavrielov, N.; Régis, J.-M.; Köster, U.; Kim, Y. H.; Esmaylzadeh, A.; Harter, A.; Jolie, J.; Knafla, L.; Ley, M.; Karayonchev, V. in Phys. Rev. C (2023). 108(3) 034310.
The A≈100 mass region is of special interest due to a rapid shape transition, observed by going from neutron number 58 to 60, especially pronounced in the Zr isotopes, where 98Zr is weakly and 100Zr is strongly deformed. To further examine this intricate phenomenon, in this work lifetimes of low-lying excited states in the nuclei 99Zr and 99Nb were determined using fast-timing techniques and an experimental setup consisting of four LaBr3(Ce) detectors. Neutron rich A=99 fragments were produced in neutron induced fission and separated by the spectrometer LOHENGRIN at the Institut Laue-Langevin in Grenoble, France. Experimental values are compared to two different calculations in the framework of the interacting boson-fermion model and discussed in the context of shape coexistence.
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Simultaneous gamma-ray and electron spectroscopy of 182,184,186Hg isotopes. Stryjczyk, M.; Andel, B.; Cubiss, J. G.; Rezynkina, K.; Rodr\'{i}guez, T. R.; Garc\'{i}a-Ramos, J. E.; Andreyev, A. N.; Pakarinen, J.; Van Duppen, P.; Antalic, S.; Berry, T.; Borge, M. J. G.; Clisu, C.; Cox, D. M.; De Witte, H.; Fraile, L. M.; Fynbo, H. O. U.; Gaffney, L. P.; Harkness-Brennan, L. J.; Huyse, M.; Illana, A.; Judson, D. S.; Konki, J.; Kurcewicz, J.; Lazarus, I.; Lica, R.; Madurga, M.; Marginean, N.; Marginean, R.; Mihai, C.; Mosat, P.; Nacher, E.; Negret, A.; Ojala, J.; Ovejas, J. D.; Page, R. D.; Papadakis, P.; Pascu, S.; Perea, A.; Podolyák, Zs.; Próchniak, L.; Pucknell, V.; Rapisarda, E.; Rotaru, F.; Sotty, C.; Tengblad, O.; Vedia, V.; Vi nals, S.; Wadsworth, R.; Warr, N.; Wrzosek-Lipska, K. in Phys. Rev. C (2023). 108(1) 014308.
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Systematic investigation of time walk and time resolution characteristics of CAEN digitizers V1730 and V1751 for application to fast-timing lifetime measurement. Harter, A.; Weinert, M.; Knafla, L.; Régis, J.-M.; Esmaylzadeh, A.; Ley, M.; Jolie, J. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2023). 1053 168356.
The timing performance of the integrated digital constant fraction discriminators of the two digitizer modules V1730 and V1751 from CAEN are systematically investigated with respect to fast-timing lifetime measurements. Systematic and parameter-dependent knowledge of the time walk behavior and the time resolution of the digital constant fraction discriminators is obtained. Understanding these dependencies is crucial for properly calibrating individual fast-timing systems and a comparable investigation of these digitizers was never conducted before. Reference is made to the existing analog standard for fast-timing techniques and recent digital developments. The study shows, that the timing performance of both modules is comparable to other digital fast-timing implementations and established fast-timing setups using analog constant fraction discriminators, but with the added benefit of digital processing. The peculiarities of the modules are pointed out and described. Both digitizer modules were found to be highly effective and user-friendly instruments for modern fast-timing requirements. Best parameter sets for both digitizers as well as best energy application ranges are provided.
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Updated analysis of the 170Er(p,t)168Er reaction data. Bucurescu, D.; Pascu, S.; Graw, G.; Hertenberger, R.; Wirth, H.-F.; Faestermann, T.; Krücken, R.; Mahgoub, M.; Jolie, J.; Brentano, P. von.; Heinze, S.; Möller, O.; Casten, R. F.; Meyer Brittingham, D. A. in Phys. Rev. C (2023). 108 014310.
More than 200 states up to 4.1 MeV excitation have been populated in 168Er with the 170Er(p,t) reaction at 25 MeV incident energy. About 80 of these states, with 0+ and 2+ assignments, were reported in a previous publication [D. Bucurescu et al., Phys. Rev. C 73, 064309 (2006)]. The present work considerably enriches the knowledge of this nucleus. A multistep coupled-channels analysis of the angular distributions is now presented for all the states observed in this experiment. Spin and parity values between 0+ and 7− are newly assigned for more than 100 states. For the states already reported in the ENSDF database with Jπ values there is a good agreement with our values. The 168Er nucleus remains one of the best experimentally known nuclei for states with low and medium spins below 4 MeV excitation energy, representing a challenge for future microscopic structure model calculations aiming to disentangle the contributions of different excitation degrees of freedom.
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Prompt gamma rays from fast neutron induced reactions on cerium and chlorine. Ophoven, Niklas; Ilic, Zeljko; Mauerhofer, Eric; Randriamalala, Tsitohaina H.; Vezhlev, Egor; Stieghorst, Christian; Révay, Zsolt; Brückel, Thomas; Jolie, Jan; Strub, Erik in Journal of Radioanalytical and Nuclear Chemistry 232 (2023) 3133 (2023). 332(8) 3133--3145.
Prompt gamma rays of cerium and chlorine were investigated with the FaNGaS (Fast Neutron-induced Gamma-ray Spectrometry) instrument operated at the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching. The gamma radiation was emitted from (n,n'), (n,p) and (n,α) reactions induced by the irradiation of a cerium(III) chloride (CeCl3) sample with a beam of fission neutrons. Additionally, a polyvinylchloride (PVC, (C2H3Cl)n) sample was irradiated to verify possible interferences between gamma lines of cerium and chlorine. We identified 87 prompt gamma lines of cerium and chlorine. From these, we assigned 58 lines to the (n,n') reaction in cerium (one for 136Ce, 41 for 140Ce and 16 for 142Ce), 23 to the (n,n') reaction in chlorine (15 for 35Cl and 8 for 37Cl), 5 lines to the 35Cl(n,p)35S reaction and 1 line to the 35Cl(n,α)32P reaction. We present relative intensities and fast-neutron spectrum-averaged partial cross sections of the aforementioned gamma lines and compare them with available literature data. Identification of new lines and discussion of possible errors adds important value to the literature data found to be consistent with our results. In addition, for a counting time of 12 h we estimate the detection limits for cerium and chlorine as 1 and 2 mg, respectively.
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Evidence of nonstatistical neutron emission following beta decay near doubly magic 132Sn. Heideman, J.; Grzywacz, R.; Xu, Z. Y.; Madurga, M.; Escher, J. E.; Kawano, T.; Algora, A.; Andreyev, A. N.; Benito, J.; Berry, T.; Borge, M. J. G.; Costache, C.; De Witte, H.; Fijalkowska, A.; Fraile, L. M.; Fynbo, H. O. U.; Gottardo, A.; Halverson, C.; Harkness-Brennan, L. J.; Illana, A.; Janiak, Ł.; Judson, D. S.; King, T. T.; Korgul, A.; Kurtukian-Nieto, T.; Lazarus, I.; Lica, R.; Lozeva, R.; Marginean, N.; Marginean, R.; Mazzocchi, C.; Mihai, C.; Mihai, R. E.; Morales, A. I.; Page, R. D.; Pakarinen, J.; Piersa-Siłkowska, M.; Podolyák, Zs.; Singh, M.; Sotty, C.; Stepaniuk, M.; Tengblad, O.; Turturica, A.; Van Duppen, P.; Vedia, V.; Vinals, S.; Warr, N.; Yokoyama, R.; Yuan, C. X. in Phys. Rev. C (2023). 108(2) 024311.
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Study of N=50 gap evolution around Z=32: new structure information for 82Ge. Thisse, D.; Lebois, M.; Verney, D.; Wilson, J. N.; Jovancević, N.; Rudigier, M.; Canavan, R.; Etasse, D.; Adsley, P.; Algora, A.; Babo, M.; Belvedere, K.; Benito, J.; Benzoni, G.; Blazhev, A.; Boso, A.; Bottoni, S.; Bunce, M.; Chakma, R.; Cieplicka-Oryńczak, N.; Courtin, S.; Cortés, M. L.; Davies, P.; Delafosse, C.; Fallot, M.; Fornal, B.; Fraile, L.; Gjestvang, D.; Gottardo, A.; Guadilla, V.; Gerst, R. B.; Häfner, G.; Hauschild, K.; Heine, M.; Henrich, C.; Homm, I.; Hommet, J.; Ibrahim, F.; Iskra, Ł. W.; Ivanov, P.; Jazrawi, S.; Korgul, A.; Koseoglou, P.; Kröll, T.; Kurtukian-Nieto, T.; Meur, L. Le; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Lozeva, R.; Matea, I.; Miernik, K.; Nemer, J.; Oberstedt, S.; Paulsen, W.; Piersa-Silkowska, M.; Poklepa, W.; Popovitch, Y.; Porzio, C.; Qi, L.; Ralet, D.; Regan, P. H.; Reygadas-Tello, D.; Rezynkina, K.; Sánchez-Tembleque, V.; Siem, S.; Schmitt, C.; Söderström, P. A.; Solak, K.; Sürder, C.; Tocabens, G.; Vedia, V.; Warr, N.; Wasilewska, B.; Wiederhold, J.; Yavahchova, M.; Zeiser, F.; Ziliani, S. in The European Physical Journal A (2023). 59(7)
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133In: A Rosetta Stone for Decays of r-Process Nuclei. Xu, Z. Y.; Madurga, M.; Grzywacz, R.; King, T. T.; Algora, A.; Andreyev, A. N.; Benito, J.; Berry, T.; Borge, M. J. G.; Costache, C.; De Witte, H.; Fijalkowska, A.; Fraile, L. M.; Fynbo, H. O. U.; Gottardo, A.; Halverson, C.; Harkness-Brennan, L. J.; Heideman, J.; Huyse, M.; Illana, A.; Janiak, \L{}.; Judson, D. S.; Korgul, A.; Kurtukian-Nieto, T.; Lazarus, I.; Licifmmode \u{a}else \u{a}\fi{}, R.; Lozeva, R.; Marginean, N.; Marginean, R.; Mazzocchi, C.; Mihai, C.; Mihai, R. E.; Morales, A. I.; Page, R. D.; Pakarinen, J.; Piersa-Si\l{}kowska, M.; Podolyák, Zs.; Sarriguren, P.; Singh, M.; Sotty, Ch.; Stepaniuk, M.; Tengblad, O.; Turturica, A.; Van Duppen, P.; Vedia, V.; Vi nals, S.; Warr, N.; Yokoyama, R.; Yuan, C. X. in Phys. Rev. Lett. (2023). 131(2) 022501.
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Beta-delayed neutron spectroscopy of 133In. Xu, Z. Y.; Madurga, M.; Grzywacz, R.; King, T. T.; Algora, A.; Andreyev, A. N.; Benito, J.; Berry, T.; Borge, M. J. G.; Costache, C.; De Witte, H.; Fijalkowska, A.; Fraile, L. M.; Fynbo, H. O. U.; Gottardo, A.; Halverson, C.; Harkness-Brennan, L. J.; Heideman, J.; Huyse, M.; Illana, A.; Janiak, \L{}.; Judson, D. S.; Korgul, A.; Kurtukian-Nieto, T.; Lazarus, I.; Licifmmode \u{a}else \u{a}\fi{}, R.; Lozeva, R.; Marginean, N.; Marginean, R.; Mazzocchi, C.; Mihai, C.; Mihai, R. E.; Morales, A. I.; Page, R. D.; Pakarinen, J.; Piersa-Si\l{}kowska, M.; Podolyák, Zs.; Sarriguren, P.; Singh, M.; Sotty, Ch.; Stepaniuk, M.; Tengblad, O.; Turturica, A.; Van Duppen, P.; Vedia, V.; Vi nals, S.; Warr, N.; Yokoyama, R.; Yuan, C. X. in Phys. Rev. C (2023). 108(1) 014314.
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The non-destructive investigation of a late antique knob bow fibula (Bügelknopffibel) from Kaiseraugst/{CH} using Muon Induced X-ray Emission ({MIXE}). Biswas, Sayani; Megatli-Niebel, Isabel; Raselli, Lilian; Simke, Ronald; Cocolios, Thomas Elias; Deokar, Nilesh; Elender, Matthias; Gerchow, Lars; Hess, Herbert; Khasanov, Rustem; Knecht, Andreas; Luetkens, Hubertus; Ninomiya, Kazuhiko; Papa, Angela; Prokscha, Thomas; Reiter, Peter; Sato, Akira; Severijns, Nathal; Shiroka, Toni; Seidlitz, Michael; Vogiatzi, Stergiani Marina; Wang, Chennan; Wauters, Frederik; Warr, Nigel; Amato, Alex in Heritage Science (2023). 11(1)
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Studying Gamow-Teller transitions and the assignment of isomeric and ground states at N = 50. Mollaebrahimi, Ali; Hornung, Christine; Dickel, Timo; Amanbayev, Daler; Kripko-Koncz, Gabriella; Plaß, Wolfgang R.; {Ayet San Andrés}, Samuel; Beck, Sönke; Blazhev, Andrey; Bergmann, Julian; Geissel, Hans; Górska, Magdalena; Grawe, Hubert; Greiner, Florian; Haettner, Emma; Kalantar-Nayestanaki, Nasser; Miskun, Ivan; Nowacki, Frédéric; Scheidenberger, Christoph; Bagchi, Soumya; Balabanski, Dimiter L.; Brencic, Ziga; Charviakova, Olga; Constantin, Paul; Dehghan, Masoumeh; Ebert, Jens; Gröf, Lizzy; Hall, Oscar; Harakeh, Muhsin N.; Kaur, Satbir; Kankainen, Anu; Knöbel, Ronja; Kostyleva, Daria A.; Kurkova, Natalia; Kuzminchuk, Natalia; Mardor, Israel; Nichita, Dragos; Otto, Jan-Hendrik; Patyk, Zygmunt; Pietri, Stephane; Purushothaman, Sivaji; Reiter, Moritz Pascal; Rink, Ann-Kathrin; Roesch, Heidi; Spătaru, Anamaria; Stanic, Goran; State, Alexandru; Tanaka, Yoshiki K.; Vencelj, Matjaz; Weick, Helmut; Winfield, John S.; Yavor, Michael I.; Zhao, Jianwei in Physics Letters B (2023). 839 137833.
Direct mass measurements of neutron-deficient nuclides around the N=50 shell closure below 100Sn were performed at the FRS Ion Catcher (FRS-IC) at GSI, Germany. The nuclei were produced by projectile fragmentation of 124Xe, separated in the fragment separator FRS and delivered to the FRS-IC. The masses of 14 ground states and two isomers were measured with relative mass uncertainties down to 1×10−7 using the multiple-reflection time-of-flight mass spectrometer of the FRS-IC, including the first direct mass measurements of 98Cd and 97Rh. A new QEC=5437±67 keV was obtained for 98Cd, resulting in a summed Gamow-Teller (GT) strength for the five observed transitions (0+⟶1+) as B(GT)=2.94−0.28+0.32. Investigation of this result in state-of-the-art shell model approaches accounting for the first time experimentally observed spectrum of GT transitions points to a perfect agreement for N=50 isotones. The excitation energy of the long-lived isomeric state in 94Rh was determined for the first time to be 293±21 keV. This, together with the shell model calculations, allows the level ordering in 94Rh to be understood.
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Lifetime measurements in low yrast states and spectroscopic peculiarities in 182Os. Harter, A.; Esmaylzadeh, A.; Knafla, L.; Fransen, C.; Spee, F. v.; Jolie, J.; Ley, M.; Karayonchev, V.; Fischer, J.; Pfeil, A. in Phys. Rev. C (2023). 108(2) 024305.
Lifetimes of the low-lying yrast states 2+,4+, and 6+ of the unstable nucleus 182Os were measured using digital fast-timing techniques. The lifetimes of the 4+ and 6+ states were determined for the first time. The remeasured value for the lifetime of the 2_1+ state was taken into account to evaluate the discrepancy between two inconsistent literature values. The lifetimes and extracted B(E2) values are presented and discussed in terms of collective signatures and transitional phenomena. The B(E2;4_1+→2_1+)/B(E2;2_1+→0_1+) ratio of 1.39(7) supports the interpretation of 182Os as a rigid rotor. This value is discussed in the context of these of the neighboring isotopes and isotones and calculations in the framework of the interacting boson model 1. Additionally, competing influences from the near lying collective deformed region,γ-soft rotors, X(5) symmetry, and neighboring regions of shape coexistence in low excitation states are assumed to influence the structure of the nucleus of interest: The trend of the excitation energies of the γ- and Kπ=0–bands in the osmium isotopic chain change remarkably at 182Os. This consideration helps to us delimit and understand the structural transitions in the isotopic and isotonic chains that intersect at 182Os.
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Axial and triaxial degrees of freedom in 72Zn. Hellgartner, S.; Mücher, D.; Wimmer, K.; Bildstein, V.; Egido, J.L.; Gernhäuser, R.; Krücken, R.; Nowak, A.K.; Zielińska, M.; Bauer, C.; Benito, M.L.L.; Bottoni, S.; {De Witte}, H.; Elseviers, J.; Fedorov, D.; Flavigny, F.; Illana, A.; Klintefjord, M.; Kröll, T.; Lutter, R.; Marsh, B.; Orlandi, R.; Pakarinen, J.; Raabe, R.; Rapisarda, E.; Reichert, S.; Reiter, P.; Scheck, M.; Seidlitz, M.; Siebeck, B.; Siesling, E.; Steinbach, T.; Stora, T.; Vermeulen, M.; Voulot, D.; Warr, N.; Wenander, F.J.C. in Physics Letters B (2023). 841 137933.
The unstable N=42 nucleus 72Zn has been studied using multiple safe Coulomb excitation in inverse kinematics. The experiment was performed at the REX-ISOLDE facility at CERN making first use of the silicon detector array C-REX in combination with the γ-ray spectrometer Miniball. The high angular coverage of C-REX allowed to determine the reduced transition strengths for the decay of the yrast 01+, 21+ and 41+ as well as of the 02+ and 22+ states in 72Zn. The quadrupole moments of the 21+, 41+ and 22+ states were extracted. Using model independent quadrupole invariants, the ground state of 72Zn was found to have an average deformation in the γ degree of freedom close to maximum triaxiality. In comparison to experimental data in zinc isotopes with N<40, the collectivity of the 41+ state in neutron-rich 72Zn is significantly larger, indicating a collective yrast band based on the ground state of 72Zn. In contrast, a low experimental B(E2;02+→21+) strength was determined, indicating a different structure for the 02+ state. Shell-model calculations propose a 02+ state featuring a larger fraction of the (spherical) N=40 closed-shell configuration in its wave function than for the 01+ ground state. The results were also compared with beyond mean field calculations which corroborate the large deformation in the γ degree of freedom, while pointing to a more deformed 02+ state. These experimental and theoretical findings establish the importance of the γ degree of freedom in the ground state of 72Zn, located between the 68,70Ni nuclei that have spherical ground states, and 76Ge, which has a rigid triaxial shape.
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Quadrupole and octupole collectivity in the semi-magic nucleus ²⁰⁶Hg. Morrison, L.; Hadyńska-Klȩk, K.; Podolyák, Zs.; Gaffney, L.P.; Zielińska, M.; Brown, B.A.; Grawe, H.; Stevenson, P.D.; Berry, T.; Boukhari, A.; Brunet, M.; Canavan, R.; Catherall, R.; Cederkäll, J.; Colosimo, S.J.; Cubiss, J.G.; Witte, H. De; Doherty, D.T.; Fransen, Ch.; Georgiev, G.; Giannopoulos, E.; Górska, M.; Hess, H.; Kaya, L.; Kröll, T.; Lalović, N.; Marsh, B.; Palenzuela, Y. Martinez; O'Neill, G.; Pakarinen, J.; Ramos, J.P.; Reiter, P.; Rodriguez, J.A.; Rosiak, D.; Rothe, S.; Rudigier, M.; Siciliano, M.; Simpson, E.C.; Snall, J.; Spagnoletti, P.; Thiel, S.; Warr, N.; Wenander, F.; Zidarova, R. in Physics Letters B (2023). 838 137675.
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Improving fast-timing time-walk calibration standards: Lifetime measurement of the 2_1+ state in 152Gd. Knafla, L.; Harter, A.; Ley, M.; Esmaylzadeh, A.; Régis, J.-M.; Bittner, D.; Blazhev, A.; {von Spee}, F.; Jolie, J. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2023). 1052 168279.
A 152Eu source was measured for 28 days using an experimental setup consisting of four LaBr3(Ce) detectors, connected to a CAEN V1730 digitizer, implementing online interpolation constant fraction discrimination for picosecond-precise timestamp determination. Using the definition of the time-walk curve, the lifetime of the 21+ (344 keV) state in 152Gd was re-measured, resulting in τ(21+)=46.9(3) ps. Compared to the previously adopted lifetime the uncertainty is reduced by an order of magnitude. This improved lifetime is of significant importance for electronic fast-timing lifetime measurements, and the impact on the systematic correction procedure and lifetime measurements in the low picosecond regime are discussed.
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Testing the predictive power of realistic shell model calculations via lifetime measurement of the 11/2+ state in 131Sb. Bottoni, S.; Gamba, E. R.; De Gregorio, G.; Gargano, A.; Leoni, S.; Fornal, B.; Brancadori, N.; Ciconali, G.; Crespi, F. C. L.; Cieplicka-Oryńczak, N.; Iskra, Ł. W.; Colombi, G.; Kim, Y. H.; Köster, U.; Michelagnoli, C.; Dunkel, F.; Esmaylzadeh, A.; Gerhard, L.; Jolie, J.; Knafla, L.; Ley, M.; Régis, J.-M.; Schomaker, K.; Sferrazza, M. in Phys. Rev. C (2023). 107(1) 014322.
The lifetime of the 11/2+1 state in the 131Sb nucleus was measured at the LOHENGRIN spectrometer of the Institut Laue-Langevin via neutron-induced fission of 235U using γ-ray fast-timing techniques. The obtained value of T1/2=3(2) ps, at the edge of the sensitivity of the experimental method, is the first result for the 11/2+1 state half-life in neutron-rich Sb isotopes. The corresponding quadrupole reduced transition probability to the ground state is B(E2)=1.4+1.5−0.6W.u., indicating a noncollective nature of this state. Realistic shell-model calculations performed in a large valence space reproduce well the experimental value and point to a dominant 2+(130Sn)⊗πg7/2 configuration for the 11/2+1 state, as expected in a weak-coupling scenario. At the same time, the sum of the quadrupole strength of the multiplet states is predicted to exceed the one of the 130Sn core as a consequence of the equal contribution of the proton and the proton-neutron quadrupole matrix elements, pointing to possible development of collectivity already in the close neighborhood of 132Sn.
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In-beam gamma-ray spectroscopy of 94Ag. Pereira-L{ó}pez, X.; Bentley, M. A.; Wadsworth, R.; Ruotsalainen, P.; Lenzi, S. M.; Forsberg, U.; Auranen, K.; Blazhev, A.; Cederwall, B.; Grahn, T.; Greenlees, P.; Illana, A.; Jenkins, D. G.; Julin, R.; Jutila, H.; Juutinen, S.; Liu, X.; Llewelyn, R.; Luoma, M.; Moschner, K.; M{ü}ller-Gatermann, C.; Singh, B. S. Nara; Nowacki, F.; Ojala, J.; Pakarinen, J.; Papadakis, P.; Rahkila, P.; Romero, J.; Sandzelius, M.; Sar{é}n, J.; Tann, H.; Uthayakumaar, S.; Uusitalo, J.; Vega-Romero, J. G.; Vilhena, J. M.; Yajzey, R.; Zhang, W.; Zimba, G. in The European Physical Journal A (2023). 59(3) 44.
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X-ray-γ fast-timing lifetime measurement of the 6_1+ state in 206Po. Stoychev, K.; Djongolov, M.; Karayonchev, V.; Rainovski, G.; Ley, M.; Jolie, J.; Bittner, D.; Blazhev, A.; Dunkel, F.; Esmaylzadeh, A.; Fransen, C.; Garbe, J.; Gerhard, L. M.; Gerst, R.-B.; Geusen, K.; Gladnishki, K. A.; Häfner, G.; Kalaydjieva, D.; Klöckner, L.; Knafla, L.; Kocheva, D.; Kornwebel, L.; Müller-Gatermann, C.; Nikodem, E.; Régis, J.-M.; Schomacker, K.; Stoyanova, M. in Phys. Rev. C (2023). 108(1) 014316.
Low-lying states in 206Po were investigated using the fast-timing technique with LaBr3(Ce) and high-purity germanium detectors. The excited states in this nucleus were populated via two consecutive electron capture decays from 206Rn. The parent isotope was produced in the 194Pt(16O,4n)206Rn fusion-evaporation reaction at the FN-Tandem facility at the Institute for Nuclear Physics, University of Cologne. The previously known value for the lifetime of the 4_1+ state in 206Po was confirmed using the generalized centroid difference (GCD) method. The lifetime of the 6_1+ state was determined from β decay in the first application of the GCD method for x-ray–γ coincidences. A Monte Carlo based approach was applied to address the indirect population of the 6_1+ state by the decay of 206At. The experimental results were examined in the context of the transition of single-particle excitations to collective behavior in the neutron-deficient Po isotopes. The obtained B(E2;6_1+→4_1+) value suggests that for the 6_1+ states in even-even Po isotopes the transition from a noncollective regime at N=126 to a collective regime occurs at N≤120.
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Spectroscopic quadrupole moments in 124Xe. Clément, E.; Lemasson, A.; Rejmund, M.; Jacquot, B.; Ralet, D.; Michelagnoli, C.; Barrientos, D.; Bednarczyk, P.; Benzoni, G.; Boston, A. J.; Bracco, A.; Cederwall, B.; Ciemala, M.; Collado, J.; Crespi, F.; Domingo-Pardo, C.; Dudouet, J.; Eberth, H. J.; de France, G.; Gadea, A.; Gonzalez, V.; Gottardo, A.; Harkness, L.; Hess, H.; Jungclaus, A.; Kaifmmode \mbox{\c{s}}else \c{s}\fi{}kaifmmode \mbox{\c{s}}else \c{s}\fi{}, A.; Korten, W.; Lenzi, S. M.; Leoni, S.; Ljungvall, J.; Menegazzo, R.; Mengoni, D.; Million, B.; Napoli, D. R.; Nyberg, J.; Podolyak, Zs.; Pullia, A.; Quintana Arnés, B.; Recchia, F.; Redon, N.; Reiter, P.; D.Salsac, M.; Sanchis, E.; ifmmode \mbox{\c{S}}else \c{S}\fi{}enyiifmmode \breve{g}else \u{g}\fi{}it, M.; Siciliano, M.; Sohler, D.; Stezowski, O.; Theisen, C.; Valiente Dobón, J. J. in Phys. Rev. C (2023). 107(1) 014324.
Background: The Xe isotopic chain with four valence protons above the \($Z=50$\) shell closure is an ideal laboratory for the study of the evolution of nuclear deformation. At the \($N=82$\) shell closure, \($^{136}\mathrm{Xe}$\) presents all characteristics of a doubly closed shell nucleus with a spherical shape. In the very neutron-deficient isotopes close to \($N=50$\), the \($\ensuremath{\alpha}$\)-decay chain of Xe was investigated to probe the radioactive decay properties near the drip-line and the magicity of \($^{100}\mathrm{Sn}$\). Additionally, the Xe isotopes present higher order symmetries in the nuclear deformation such as the octupole degree of freedom near \($N=60$\) and \($N=90$\) or O(6) symmetry in stable isotopes.Purpose: The relevance of the O(6) symmetry has been investigated by measuring the spectroscopic quadrupole moment of the first excited states in \($^{124}\mathrm{Xe}$\). In the O(6) symmetry limit, the spectroscopic quadrupole moment of collective states is expected to be null.Method: A stable \($^{124}\mathrm{Xe}$\) beam with energies of \($4.03A$\) MeV and \($4.11A$\) MeV was used to bombard a \(${}^{\mathrm{nat}}\mathrm{W}$\) target at the GANIL facility. Excited states were populated via the safe Coulomb excitation reaction. The collision of the heavy ions with a large \($Z$\) at low energy make this reaction sensitive to the diagonal \($E2$\) matrix element of the excited states. The recoils were detected in the \($\mathrm{VAMOS}++$\) magnetic spectrometer and the \($\ensuremath{\gamma}$\) rays in the AGATA tracking array. The least squares fitting code gosia was used for the analysis to extract both \($E2$\) and \($M1$\) transitional and \($E2$\) diagonal matrix elements.Results: The rotational ground state band was populated up to the \(${8}_{1}^{+}$\) state as well as the \(${2}_{2}^{+}$\) and \(${4}_{2}^{+}$\) states. Using high precision spectroscopic data to constrain the gosia fit, the spectroscopic quadrupole moments of the \(${2}_{1}^{+}$\), \(${4}_{1}^{+}$\), and \(${6}_{1}^{+}$\) states were determined for the first time.Conclusions: The spectroscopic quadrupole moments were found to be negative, large, and constant in the ground state band underlining the prolate axially deformed ground state band of \($^{124}\mathrm{Xe}$\). The present experimental data confirm that the O(6) symmetry is substantially broken in \($^{124}\mathrm{Xe}$\).
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Coulomb excitation of ²²²Rn. Spagnoletti, P.; Butler, P. A.; Gaffney, L. P.; Abrahams, K.; Bowry, M.; Cederkäll, J.; Chupp, T.; de Angelis, G.; De Witte, H.; Garrett, P. E.; Goldkuhle, A.; Henrich, C.; Illana, A.; Johnston, K.; Joss, D. T.; Keatings, J. M.; Kelly, N. A.; Komorowska, M.; Konki, J.; Kröll, T.; Lozano, M.; Singh, B. S. Nara; O'Donnell, D.; Ojala, J.; Page, R. D.; Pedersen, L. G.; Raison, C.; Reiter, P.; Rodriguez, J. A.; Rosiak, D.; Rothe, S.; Scheck, M.; Seidlitz, M.; Shneidman, T. M.; Siebeck, B.; Sinclair, J.; Smith, J. F.; Stryjczyk, M.; Van Duppen, P.; Viñals, S.; Virtanen, V.; Wrzosek-Lipska, K.; Warr, N.; Zielińska, M. in Phys. Rev. C (2022). 105(2) 024323.
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Characterization of a Continuous Muon Source for the Non-Destructive and Depth-Selective Elemental Composition Analysis by Muon Induced X- and Gamma-rays. Biswas, Sayani; Gerchow, Lars; Luetkens, Hubertus; Prokscha, Thomas; Antognini, Aldo; Berger, Niklaus; Cocolios, Thomas Elias; Dressler, Rugard; Indelicato, Paul; Jungmann, Klaus; Kirch, Klaus; Knecht, Andreas; Papa, Angela; Pohl, Randolf; Pospelov, Maxim; Rapisarda, Elisa; Reiter, Peter; Ritjoho, Narongrit; Roccia, Stephanie; Severijns, Nathal; Skawran, Alexander; Vogiatzi, Stergiani Marina; Wauters, Frederik; Willmann, Lorenz; Amato, Alex in Applied Sciences (2022). 12(5) 2541.
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Lifetime measurements in the ground-state band in ¹⁰⁴Pd. Droste, M.; Blazhev, A.; Reiter, P.; Arnswald, K.; Beckers, M.; Fransen, C.; Hetzenegger, R.; Hirsch, R.; Kaya, L.; Knafla, L.; Lewandowski, L.; Müller-Gatermann, C.; Petkov, P.; Rosiak, D.; Seidlitz, M.; Siebeck, B.; Vogt, A.; Warr, N.; Wolf, K. in Phys. Rev. C (2022). 106(2) 024329.
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Evidence of Partial Seniority Conservation in the πg9/2 Shell for the N=50 Isotones. Pérez-Vidal, R. M.; Gadea, A.; Domingo-Pardo, C.; Gargano, A.; Valiente-Dobón, J. J.; Clément, E.; Lemasson, A.; Coraggio, L.; Siciliano, M.; Szilner, S.; Bast, M.; Braunroth, T.; Collado, J.; Corina, A.; Dewald, A.; Doncel, M.; Dudouet, J.; de France, G.; Fransen, C.; González, V.; Hüyük, T.; Jacquot, B.; John, P. R.; Jungclaus, A.; Kim, Y. H.; Korichi, A.; Labiche, M.; Lenzi, S.; Li, H.; Ljungvall, J.; López-Martens, A.; Mengoni, D.; Michelagnoli, C.; Müller-Gatermann, C.; Napoli, D. R.; Navin, A.; Quintana, B.; Ramos, D.; Rejmund, M.; Sanchis, E.; Simpson, J.; Stezowski, O.; Wilmsen, D.; Zielińska, M.; Boston, A. J.; Barrientos, D.; Bednarczyk, P.; Benzoni, G.; Birkenbach, B.; Boston, H. C.; Bracco, A.; Cederwall, B.; Cullen, D. M.; Didierjean, F.; Eberth, J.; Gottardo, A.; Goupil, J.; Harkness-Brennan, L. J.; Hess, H.; Judson, D. S.; Kaşkaş, A.; Korten, W.; Leoni, S.; Menegazzo, R.; Million, B.; Nyberg, J.; Podolyak, Zs.; Pullia, A.; Ralet, D.; Recchia, F.; Reiter, P.; Rezynkina, K.; Salsac, M. D.; Şenyiğit, M.; Sohler, D.; Theisen, Ch.; Verney, D. in Phys. Rev. Lett. (2022). 129(11) 112501.
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Evidence for spherical-oblate shape coexistence in ⁸⁷Tc. Liu, X.; Cederwall, B.; Qi, C.; Wyss, R. A.; Aktas, Ö.; Ertoprak, A.; Zhang, W.; Clément, E.; de France, G.; Ralet, D.; Gadea, A.; Goasduff, A.; Jaworski, G.; Kuti, I.; Nyakó, B. M.; Nyberg, J.; Palacz, M.; Wadsworth, R.; Valiente-Dobón, J. J.; Al-Azri, H.; Ataç Nyberg, A.; Bäck, T.; de Angelis, G.; Doncel, M.; Dudouet, J.; Gottardo, A.; Jurado, M.; Ljungvall, J.; Mengoni, D.; Napoli, D. R.; Petrache, C. M.; Sohler, D.; Timár, J.; Barrientos, D.; Bednarczyk, P.; Benzoni, G.; Birkenbach, B.; Boston, A. J.; Boston, H. C.; Burrows, I.; Charles, L.; Ciemala, M.; Crespi, F. C. L.; Cullen, D. M.; Désesquelles, P.; Domingo-Pardo, C.; Eberth, J.; Erduran, N.; Ertürk, S.; González, V.; Goupil, J.; Hess, H.; Huyuk, T.; Jungclaus, A.; Korten, W.; Lemasson, A.; Leoni, S.; Maj, A.; Menegazzo, R.; Million, B.; Perez-Vidal, R. M.; Podolyàk, Zs.; Pullia, A.; Recchia, F.; Reiter, P.; Saillant, F.; Salsac, M. D.; Sanchis, E.; Simpson, J.; Stezowski, O.; Theisen, C.; Zielińska, M. in Phys. Rev. C (2022). 106(3) 034304.
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New narrow resonances observed in the unbound nucleus ¹⁵F. Girard-Alcindor, V.; Mercenne, A.; Stefan, I.; de Oliveira Santos, F.; Michel, N.; Płoszajczak, M.; Assié, M.; Lemasson, A.; Clément, E.; Flavigny, F.; Matta, A.; Ramos, D.; Rejmund, M.; Dudouet, J.; Ackermann, D.; Adsley, P.; Assunção, M.; Bastin, B.; Beaumel, D.; Benzoni, G.; Borcea, R.; Boston, A. J.; Brugnara, D.; Cáceres, L.; Cederwall, B.; Celikovic, I.; Chudoba, V.; Ciemala, M.; Collado, J.; Crespi, F. C. L.; D'Agata, G.; De France, G.; Delaunay, F.; Diget, C.; Domingo-Pardo, C.; Eberth, J.; Fougères, C.; Franchoo, S.; Galtarossa, F.; Georgiadou, A.; Gibelin, J.; Giraud, S.; González, V.; Goyal, N.; Gottardo, A.; Goupil, J.; Grévy, S.; Guimaraes, V.; Hammache, F.; Harkness-Brennan, L. J.; Hess, H.; Jovančević, N.; Judson Oliver, D. S.; Kamalou, O.; Kamenyero, A.; Kiener, J.; Korten, W.; Koyama, S.; Labiche, M.; Lalanne, L.; Lapoux, V.; Leblond, S.; Lefevre, A.; Lenain, C.; Leoni, S.; Li, H.; Lopez-Martens, A.; Maj, A.; Matea, I.; Menegazzo, R.; Mengoni, D.; Meyer, A.; Million, B.; Monteagudo, B.; Morfouace, P.; Mrazek, J.; Niikura, M.; Piot, J.; Podolyak, Zs.; Portail, C.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Rezynkina, K.; Roger, T.; Rojo, J. S.; Rotaru, F.; Salsac, M. D.; Sánchez Benítez, A. M.; Sanchis, E.; Şienyigit, M.; de Séréville, N.; Siciliano, M.; Simpson, J.; Sohler, D.; Sorlin, O.; Stanoiu, M.; Stodel, C.; Suzuki, D.; Theisen, C.; Thisse, D.; C.Thomas, J.; Ujic, P.; Valiente-Dobón, J. J.; Zielińska, M. in Phys. Rev. C (2022). 105(5) L051301.
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The DESPEC setup for GSI and FAIR. Mistry, A.K.; Albers, H.M.; Arıcı, T.; Banerjee, A.; Benzoni, G.; Cederwall, B.; Gerl, J.; Górska, M.; Hall, O.; Hubbard, N.; Kojouharov, I.; Jolie, J.; Martinez, T.; Podolyák, Zs.; Regan, P.H.; Tain, J.L.; Tarifeno-Saldivia, A.; Schaffner, H.; Werner, V.; Ağgez, G.; Agramunt, J.; Ahmed, U.; Aktas, O.; Alcayne, V.; Algora, A.; Alhomaidhi, S.; Amjad, F.; Appleton, C.; Armstrong, M.; Balogh, M.; Banerjee, K.; Bednarczyk, P.; Benito, J.; Bhattacharya, C.; Black, P.; Blazhev, A.; Bottoni, S.; Boutachkov, P.; Bracco, A.; Bruce, A.M.; Brunet, M.; Bruno, C.G.; Burrows, I.; Calvino, F.; Canavan, R.L.; Cano-Ott, D.; Chishti, M.M.R.; Coleman-Smith, P.; Cortés, M.L.; Cortes, G.; Crespi, F.; Das, B.; Davinson, T.; De Blas, A.; Dickel, T.; Doncel, M.; Ertoprak, A.; Esmaylzadeh, A.; Fornal, B.; Fraile, L.M.; Galtarossa, F.; Gottardo, A.; Guadilla, V.; Ha, J.; Haettner, E.; Häfner, G.; Heggen, H.; Herrmann, P.; Hornung, C.; Jazrawi, S.; John, P.R.; Jokinen, A.; Jones, C.E.; Kahl, D.; Karayonchev, V.; Kazantseva, E.; Kern, R.; Knafla, L.; Knöbel, R.; Koseoglou, P.; Kosir, G.; Kostyleva, D.; Kurz, N.; Kuzminchuk, N.; Labiche, M.; Lawson, J.; Lazarus, I.; Lenzi, S.M.; Leoni, S.; Llanos-Expósito, M.; Lozeva, R.; Maj, A.; Meena, J.K.; Mendoza, E.; Menegazzo, R.; Mengoni, D.; Mertzimekis, T.J.; Mikolajczuk, M.; Million, B.; Mont-Geli, N.; Morales, A.I.; Morral, P.; Mukha, I.; Murias, J.R.; Nacher, E.; Napiralla, P.; Napoli, D.R.; Nara-Singh, B.S.; O’Donnell, D.; Orrigo, S.E.A.; Page, R.D.; Palit, R.; Pallas, M.; Pellumaj, J.; Pelonis, S.; Pentilla, H.; Pérez de Rada, A.; Pérez-Vidal, R.M.; Petrache, C.M.; Pietralla, N.; Pietri, S.; Pigliapoco, S.; Plaza, J.; Polettini, M.; Porzio, C.; Pucknell, V.F.E.; Recchia, F.; Reiter, P.; Rezynkina, K.; Rinta-Antila, S.; Rocco, E.; Rösch, H.A.; Roy, P.; Rubio, B.; Rudigier, M.; Ruotsalainen, P.; Saha, S.; Şahin, E.; Scheidenberger, Ch.; Seddon, D.A.; Sexton, L.; Sharma, A.; Si, M.; Simpson, J.; Smith, A.; Smith, R.; Söderström, P.A.; Sood, A.; Soylu, A.; Tanaka, Y.K.; Valiente-Dobón, J.J.; Vasileiou, P.; Vasiljevic, J.; Vesic, J.; Villamarin, D.; Weick, H.; Wiebusch, M.; Wiederhold, J.; Wieland, O.; Wollersheim, H.J.; Woods, P.J.; Yaneva, A.; Zanon, I.; Zhang, G.; Zhao, J.; Zidarova, R.; Zimba, G.; Zyriliou, A. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2022). 1033 166662.
The DEcay SPECtroscopy (DESPEC) setup for nuclear structure investigations was developed and commissioned at GSI, Germany in preparation for a full campaign of experiments at the FRS and Super-FRS. In this paper, we report on the first employment of the setup in the hybrid configuration with the AIDA implanter coupled to the FATIMA LaBr3(Ce) fast-timing array, and high-purity germanium detectors. Initial results are shown from the first experiments carried out with the setup. An overview of the setup and function is discussed, including technical advancements along the path.
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Development of a new γ–γ angular correlation analysis method using a symmetric ring of clover detectors. Knafla, L.; Esmaylzadeh, A.; Harter, A.; Jolie, J.; Köster, U.; Ley, M.; Michelagnoli, C.; Régis, J.-M. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2022). 1042 167463.
A new method for γ–γ angular correlation analysis using a symmetric ring of HPGe clover detectors is presented. Pairwise combinations of individual crystals are grouped based on the geometric properties of the spectrometer, constrained by a single variable parameterization based on symmetry considerations. The corresponding effective interaction angles between crystal pairs, as well as the attenuation coefficients are extracted directly from the measured experimental data. Angular correlation coefficients, parameter uncertainties and parameter co-variances are derived using a Monte-Carlo approach, considering all sources of statistical uncertainty. The general applicability of this approach is demonstrated by reproducing known multipole mixing ratios in 177Hf, 152Gd and 116Sn, populated by either β-decay or (n, γ)-reactions, measured at the Institut Laue-Langevin, using the EXILL&FATIMA spectrometer and different configurations of the FIPPS instrument. The derived mixing ratios are in excellent agreement with adopted literature values with comparable or better precision.
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Gamma-ray spectroscopy of low-lying yrast and non-yrast states in neutron-rich 94,95,96Kr. Gerst, R.-B.; Blazhev, A.; Moschner, K.; Doornenbal, P.; Obertelli, A.; Nomura, K.; Ebran, J.-P.; Hilaire, S.; Libert, J.; Authelet, G.; Baba, H.; Calvet, D.; Château, F.; Chen, S.; Corsi, A.; Delbart, A.; Gheller, J.-M.; Giganon, A.; Gillibert, A.; Lapoux, V.; Motobayashi, T.; Niikura, M.; Paul, N.; Roussé, J.-Y.; Sakurai, H.; Santamaria, C.; Steppenbeck, D.; Taniuchi, R.; Uesaka, T.; Ando, T.; Arici, T.; Browne, F.; Bruce, A. M.; Caroll, R.; Chung, L. X.; Cortés, M. L.; Dewald, M.; Ding, B.; Flavigny, F.; Franchoo, S.; Górska, M.; Gottardo, A.; Jolie, J.; Jungclaus, A.; Lee, J.; Lettmann, M.; Linh, B. D.; Liu, J.; Liu, Z.; Lizarazo, C.; Momiyama, S.; Nagamine, S.; Nakatsuka, N.; Nita, C. R.; Nobs, C.; Olivier, L.; Orlandi, R.; Patel, Z.; Podolyák, Zs.; Rudigier, M.; Saito, T.; Shand, C.; Söderström, P.-A.; Stefan, I.; Vaquero, V.; Werner, V.; Wimmer, K.; Xu, Z. in Phys. Rev. C (2022). 105(2) 024302.
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Investigation of gamma softness: Lifetime measurements in 104,106Ru. Esmaylzadeh, A.; Blazhev, A.; Nomura, K.; Jolie, J.; Beckers, M.; Fransen, C.; Gerst, R.-B.; Harter, A.; Karayonchev, V.; Knafla, L.; Ley, M.; von Spee, F. in Phys. Rev. C (2022). 106(6) 064323.
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Lifetime measurements in the tungsten isotopes 176,178,180W. Harter, A.; Knafla, L.; Frießner, G.; Häfner, G.; Jolie, J.; Blazhev, A.; Dewald, A.; Dunkel, F.; Esmaylzadeh, A.; Fransen, C.; Karayonchev, V.; Lawless, K.; Ley, M.; Régis, J.-M.; Zell, K. O. in Phys. Rev. C (2022). 106(2) 024326.
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Nature of seniority symmetry breaking in the semimagic nucleus 94Ru. Das, B.; Cederwall, B.; Qi, C.; Górska, M.; Regan, P. H.; Aktas, Ö.; Albers, H. M.; Banerjee, A.; Chishti, M. M. R.; Gerl, J.; Hubbard, N.; Jazrawi, S.; Jolie, J.; Mistry, A. K.; Polettini, M.; Yaneva, A.; Alhomaidhi, S.; Zhao, J.; Arici, T.; Bagchi, S.; Benzoni, G.; Boutachkov, P.; Davinson, T.; Dickel, T.; Haettner, E.; Hall, O.; Hornung, Ch.; Hucka, J. P.; John, P. R.; Kojouharov, I.; Knöbel, R.; Kostyleva, D.; Kuzminchuk, N.; Mukha, I.; Plass, W. R.; Nara Singh, B. S.; Vasiljevi ́c, J.; Pietri, S.; Podolyák, Zs.; Rudigier, M.; Rösch, H.; Sahin, E.; Schaffner, H.; Scheidenberger, C.; Schirru, F.; Sharma, A.; Shearman, R.; Tanaka, Y.; Vesi ́c, J.; Weick, H.; Wollersheim, H. J.; Ahmed, U.; Algora, A.; Appleton, C.; Benito, J.; Blazhev, A.; Bracco, A.; Bruce, A. M.; Brunet, M.; Canavan, R.; Esmaylzadeh, A.; Fraile, L. M.; Häfner, G.; Heggen, H.; Kahl, D.; Karayonchev, V.; Kern, R.; Korgul, A.; Kosir, G.; Kurz, N.; Lozeva, R.; Mikolajczuk, M.; Napiralla, P.; Page, R.; Petrache, C. M.; Pietralla, N.; Régis, J.-M.; Ruotsalainen, P.; Sexton, L.; Sanchez-Temble, V.; Si, M.; Vilhena, J.; Werner, V.; Wiederhold, J.; Witt, W.; Woods, P. J.; Zimba, G. in Phys. Rev. C (2022). 105(3) L031304.
Direct lifetime measurements via γ−γ coincidences using a fast timing detector array consisting of LaBr3(Ce) scintillators has been applied to determine the lifetime of low-lying states in the semimagic (N=50) nucleus 94Ru. The experiment was carried out as the first in a series of “FAIR-0” experiments with the DESPEC experimental setup at the Facility for Antiproton and Ion Research (FAIR). Excited states in 94Ru were populated primarily via the β-delayed proton emission of 95Pd nuclei, produced in the projectile fragmentation of an 850 MeV/nucleon 124Xe beam impinging on a 4 g/cm29Be target. While the deduced E2 strength for the 2+→0+ transition in the yrast cascade follows the expected behavior for conserved seniority symmetry, the intermediate 4+→2+ transition exhibits a drastic enhancement of transition strength in comparison with pure-seniority model predictions as well as standard shell model predictions in the fpg proton hole space with respect to doubly magic 100Sn. The anomalous behavior is ascribed to a subtle interference between the wave function of the lowest seniority ν=2, Iπ=4+ state and that of a close-lying ν=4 state that exhibits partial dynamic symmetry. In addition, the observed strongly prohibitive 6+→4+ transition can be attributed to the same mechanism but with a destructive interference. It is noted that such effects may provide stringent tests of the nucleon-nucleon interactions employed in state-of-the-art theoretical model calculations.
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Lifetime measurements in 80Br and a new region for observation of chiral electromagnetic selection rules. Guo, R.J.; Wang, S.Y.; Schwengner, R.; Xu, W.Z.; Qi, B.; Liu, C.; Rohilla, A.; Dönau, F.; Servene, T.; Schnare, H.; Reif, J.; Winter, G.; Käubler, L.; Prade, H.; Skoda, S.; Eberth, J.; Thomas, H.G.; Becker, F.; Fiedler, B.; Freund, S.; Kasemann, S.; Steinhardt, T.; Thelen, O.; Härtlein, T.; Ender, C.; Köck, F.; Reiter, P.; Schwalm, D. in Phys. Lett. B. (2022). 833 137344.
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Competition between allowed and first-forbidden beta decays of 208At and expansion of the 208Po level scheme. Brunet, M.; Podolyák, Zs.; Berry, T. A.; Brown, B. A.; Carroll, R. J.; Lica, R.; Sotty, Ch.; Andreyev, A. N.; Borge, M. J. G.; Cubiss, J. G.; Fraile, L. M.; Fynbo, H. O. U.; Gamba, E.; Greenlees, P.; Harkness-Brennan, L. J.; Huyse, M.; Judson, D. S.; Konki, J.; Kurcewicz, J.; Lazarus, I.; Madurga, M.; Marginean, N.; Marginean, R.; Marroquin, I.; Mihai, C.; Nácher, E.; Negret, A.; Pascu, S.; Page, R. D.; Perea, A.; Phrompao, J.; Piersa, M.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Regan, P. H.; Rotaru, F.; Rudigier, M.; Shand, C. M.; Shearman, R.; Simpson, E. C.; Stora, T.; Tengblad, O.; Van Duppen, P.; Vedia, V.; Vinals, S.; Wadsworth, R.; Warr, N.; De Witte, H. in Phys. Rev. C (2021). 103(5) 054327.
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In search of nano-materials with enhanced secondary electron emission for radiation detectors. Cholewa, M;; Cappellazzo, M;; Ley, M;; Bittner, D;; Jolie, J;; Lee, K;; Song, M;; Yi, G;; Boutachkov, P; in Nature Scientific Reports (2021). 11(10517)
There has been limited research devoted to secondary electron emission (SEE) from nano-materials using rapid and heavy ion bombardment. Here we report a comparison of SEE properties between novel nano-materials with a three-dimensional nano-structure composed of a mostly regular pattern of rods and gold used as a standard material for SEE under bombardment of heavy ions at energies of a few MeV/nucleon. The nano-structured materials show enhanced SEE properties when compared with gold. Results from this work will enable the development of new radiation detectors for science and industry.
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Triaxiality in the mid-shell nucleus 112Pd. Esmaylzadeh, A.; Karayonchev, V.; Häfner, G.; Jolie, J.; Beckers, M.; Blazhev, A.; Dewald, A.; Fransen, C.; Goldkuhle, A.; Knafla, L.; Müller-Gatermann, C. in Phys. Rev. C (2021). 103(5) 054324.
Lifetimes of low-spin excited states in 112Pd were measured using the recoil-distance Doppler-shift technique. The nucleus of interest was populated in a 110 Pd(18O,16O)112Pd reaction using the Cologne FN Tandem accelerator. Three lifetimes of ground-state band members and one lifetime of the γ band were measured. From these lifetimes reduced transition probabilities were extracted and compared to interacting boson model, γ-soft calculations, and Davydov calculations. The lifetime of the 2+γ gives some insights on the nuclear shape and structure of the γ band. The deduced transition rates show an indicator for a rigid triaxial nucleus as well as more indicators for a γ-soft nucleus.
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Lifetime measurements in 182Pt using γ–γ fast-timing. Häfner, G.; Esmaylzadeh, A.; Jolie, J.; Régis, J.-M.; Müller-Gatermann, C.; Blazhev, A.; Fransen, C.; Gerst, R.-B.; Karayonchev, V.; Knafla, L.; Saed-Samii, N.; Zell, K.-O. in The European Physical Journal A (2021). 57(5) 174.
The level lifetimes of the 2+1 and 4+1 states in 182Pt have been re-measured employing the γ–γ fast-timing technique using fast LaBr3(Ce) scintillators. Excited states in the nucleus of interest were populated by the fusion-evaporation reaction 170Yb(16O,4n)182Pt at a beam energy of 87 MeV provided by the FN Tandem accelerator of the University of Cologne. The lifetime of the 2+1 state was re-measured with high accuracy to be τ=563(12) ps and resolves inconsistencies from previous measurements. Experimental results are compared to theoretical calculations in the framework of the sd-IBM with and without configuration mixing.
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Microscopic structure of the one-phonon 2+ states of 208Po. Kalaydjieva, D.; Kocheva, D.; Rainovski, G.; Karayonchev, V.; Jolie, J.; Pietralla, N.; Beckers, M.; Blazhev, A.; Dewald, A.; Djongolov, M.; Esmaylzadeh, A.; Fransen, C.; Gladnishki, K. A.; Goldkuhle, A.; Henrich, C.; Homm, I.; Ide, K. E.; John, P. R.; Kern, R.; Kleemann, J.; Kröll, Th.; Müller-Gatermann, C.; Scheck, M.; Spagnoletti, P.; Stoyanova, M.; Stoychev, K.; Werner, V.; Yaneva, A.; Dimitrova, S. S.; De Gregorio, G.; Naïdja, H.; Gargano, A. in Phys. Rev. C (2021). 104(2) 024311.
The lifetimes of the 2+1 and 4+1 states of 208Po were measured in the α-transfer reaction 204Pb(12C,8Be)208Po by γ-ray spectroscopy utilizing the recoil distance Doppler shift method. The newly extracted transition strengths alongside ones of the decay of the 2+2 state were compared to the results of large-scale shell-model calculations using an effective interaction derived from the realistic CD-Bonn nucleon-nucleon potential. The comparison indicates the importance of the quadrupole isovector excitations in the valence shell for a fine tuning of the two-body matrix elements of the shell-model interaction.
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Gamma spectroscopy with AGATA in its first phases: New insights in nuclear excitations along the nuclear chart. Bracco, A.; Duchêne, G.; Podolyák, Zs.; Reiter, P. in Progress in Particle and Nuclear Physics (2021). 121 103887.
The Advanced GAmma Tracking Array (AGATA), the new generation high-resolution γ-ray spectrometer, has seen the realization of the first phases of its construction and exploitation. A number of nuclear structure studies based on experiments utilizing the principle of γ-ray tracking were carried out in this decade. The combination of highest detection efficiency and position sensitivity allowed very selective spectroscopic studies with stable beams and the use of instable ion beams with the lowest intensities. Nuclear-structure studies commenced already at INFN-LNL (Legnaro, Italy) with a first implementation of the array consisting of five AGATA modules. A larger array of AGATA modules was used at GSI (Darmstadt, Germany) for experiments with unstable ion beams at relativistic energies. The spectrometer was then mounted in a beam line at GANIL (Caen, France). This review discusses several of the obtained results, underlying the progress made and future perspectives. The performed experiments give insights into nuclear structure issues which are connected to single particles, collective degrees of freedom, nucleon interactions and symmetries. Most of the investigated nuclei are located outside the stability line and for stable nuclei the investigations concern unexplored configurations. Altogether the obtained results represent advances which could test theory in exclusive way and motivate new theoretical developments. Opportunities for further γ-ray spectroscopy with the foreseen more advanced phase of the AGATA emerge in the discussions of the presented data.
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Evidence for enhanced neutron-proton correlations from the level structure of the N=Z+1 nucleus ₄₃⁸⁷Tc₄₄. Liu, X.; Cederwall, B.; Qi, C.; Wyss, R. A.; Aktas, Ö.; Ertoprak, A.; Zhang, W.; Clément, E.; de France, G.; Ralet, D.; Gadea, A.; Goasduff, A.; Jaworski, G.; Kuti, I.; Nyakó, B. M.; Nyberg, J.; Palacz, M.; Wadsworth, R.; Valiente-Dobón, J. J.; Al-Azri, H.; Ataç Nyberg, A.; Bäck, T.; de Angelis, G.; Doncel, M.; Dudouet, J.; Gottardo, A.; Jurado, M.; Ljungvall, J.; Mengoni, D.; Napoli, D. R.; Petrache, C. M.; Sohler, D.; Timár, J.; Barrientos, D.; Bednarczyk, P.; Benzoni, G.; Birkenbach, B.; Boston, A. J.; Boston, H. C.; Burrows, I.; Charles, L.; Ciemala, M.; Crespi, F. C. L.; Cullen, D. M.; Désesquelles, P.; Domingo-Pardo, C.; Eberth, J.; Erduran, N.; Ertürk, S.; González, V.; Goupil, J.; Hess, H.; Huyuk, T.; Jungclaus, A.; Korten, W.; Lemasson, A.; Leoni, S.; Maj, A.; Menegazzo, R.; Million, B.; Perez-Vidal, R. M.; Podolyàk, Zs.; Pullia, A.; Recchia, F.; Reiter, P.; Saillant, F.; Salsac, M. D.; Sanchis, E.; Simpson, J.; Stezowski, O.; Theisen, C.; Zielińska, M. in Phys. Rev. C (2021). 104(2) L021302.
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Reinterpretation of excited states in 212Po: Shell-model multiplets rather than α-cluster states. Fernández, A.; Jungclaus, A.; Golubev, P.; Rudolph, D.; Sarmiento, L. G.; Gargano, A.; Naïdja, H.; Astier, A.; Dupont, E.; Gadea, A.; Nácher, E.; Perea, A.; Wimmer, K.; Clément, E.; Fremont, G.; Goupil, J.; Houarner, C.; Jacquot, B.; Korichi, A.; Lemasson, A.; Li, H. J.; Ljungvall, J.; Ménager, L.; Pérez-Vidal, R. M.; Petrache, C. M.; Ralet, D.; Ropert, J. A.; Saillant, F.; Såmark-Roth, A.; Simpson, G. S.; Spitaels, C.; Zielinska, M.; Ansari, S.; Dudouet, J.; Illana, A.; Jurado, M.; Kocheva, D.; Lalović, N.; Lorenz, Ch.; Quintana, B.; Rainovski, G.; Redon, N.; Tocabens, G.; Barrientos, D.; Benzoni, G.; Birkenbach, B.; Boston, A. J.; Boston, H. C.; Bracco, A.; Ciemala, M.; Collado, J.; Cullen, D. M.; Domingo-Pardo, C.; Eberth, J.; González, V.; Harkness-Brennan, L. J.; Hess, H.; Judson, D. S.; Korten, W.; Leoni, S.; Maj, A.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Million, B.; Napoli, D. R.; Nyberg, J.; Podolyak, Zs.; Pullia, A.; Reiter, P.; Sanchis, E.; Stezowski, O.; Theisen, Ch.; Valiente-Dobón, J. J. in Phys. Rev. C (2021). 104(5) 054316.
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Lifetime measurements to investigate γ softness and shape coexistence in 102Mo. Esmaylzadeh, A.; Karayonchev, V.; Nomura, K.; Jolie, J.; Beckers, M.; Blazhev, A.; Dewald, A.; Fransen, C.; Gerst, R.-B.; Häfner, G.; Harter, A.; Knafla, L.; Ley, M.; Robledo, L. M.; Rodríguez-Guzmán, R.; Rudigier, M. in Phys. Rev. C (2021). 104(6) 064314.
Lifetimes of low-spin excited states in 102Mo populated in a 100Mo(18O,16O)102Mo two-neutron transfer reaction were measured using the recoil-distance Doppler-shift technique at the Cologne FN Tandem accelerator. Lifetimes of the 2+1, 4+1, 6+1, 0+2, 2+γ, 3+γ states and one upper limit for the lifetime of the 4+γ state were obtained. The energy levels and deduced electromagnetic transition probabilities are compared with those obtained within the mapped interacting boson model framework with microscopic input from Gogny mean-field calculations. With the newly obtained signatures a more detailed insight in the γ softness and shape coexistence in 102Mo is possible and discussed in the context of the Z≈40 and N≈60 region. The nucleus of 102Mo follows the γ soft trend of the Mo isotopes. The properties of the 0+2 state indicate, in contrast with the microscopic predictions, shape coexistence which also occurs in other N=60 isotones.
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The (6+) isomer in 102Sn revisited: Neutron and proton effective charges close to the double shell closure. Grawe, H.; Straub, K.; Faestermann, T.; Górska, M.; Hinke, C.; Krücken, R.; Nowacki, F.; Böhmer, M.; Boutachkov, P.; Geissel, H.; Gernhäuser, R.; Gottardo, A.; Grȩbosz, J.; Kurz, N.; Liu, Z.; Maier, L.; Pietri, S.; Podolyák, Zs.; Steiger, K.; Weick, H.; Wollersheim, H.J.; Woods, P.J.; Al-Dahan, N.; Alkhomashi, N.; Ataç, A.; Blazhev, A.; Braun, N.; Čeliković, I.; Davinson, T.; Dillmann, I.; Domingo-Pardo, C.; Doornenbal, P.; Farrelly, G.; Farinon, F.; {de France}, G.; Gerl, J.; Goel, N.; Habermann, T.; Hoischen, R.; Janik, R.; Karny, M.; Kaşkaş, A.; Kojouharov, I.; Kröll, Th.; Lewitowicz, M.; Litvinov, Yu.A.; Myalski, S.; Nebel, F.; Nishimura, S.; Nociforo, C.; Nyberg, J.; Parikh, A.; Procházka, A.; Regan, P.H.; Rigollet, C.; Schaffner, H.; Scheidenberger, C.; Schwertel, S.; Söderström, P.-A.; Steer, S.; Stolz, A.; Strmeň, P. in Physics Letters B (2021). 820 136591.
In a high-energy fragmentation experiment at GSI an I=π(6+) isomer and its γ-decay are identified in 102Sn, the two-neutron neighbour of the doubly-magic 100Sn. Its half-life is measured to be T=1/2367(11) ns. The possible existence of further isomers is discussed in the framework of large-scale shell model (LSSM) calculations including up to five particle-hole excitations of the 100Sn core. From the precise B(E2; 6+→4+) strength and the recently remeasured value for B(E2; 8+→6+) in the two-proton hole neighbour 98Cd effective E2 polarization charges for protons and neutrons were inferred including LSSM corrections within the full N=4 0ħω space. The results are discussed in comparison to predicted and empirically determined effective operators.
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Spectroscopy along Flerovium Decay Chains: Discovery of ²⁸⁰Ds and an Excited State in ²⁸²Cn. Såmark-Roth, A.; Cox, D. M.; Rudolph, D.; Sarmiento, L. G.; Carlsson, B. G.; Egido, J. L.; Golubev, P.; Heery, J.; Yakushev, A.; Åberg, S.; Albers, H. M.; Albertsson, M.; Block, M.; Brand, H.; Calverley, T.; Cantemir, R.; Clark, R. M.; Düllmann, Ch. E.; Eberth, J.; Fahlander, C.; Forsberg, U.; Gates, J. M.; Giacoppo, F.; Götz, M.; Götz, S.; Herzberg, R.-D.; Hrabar, Y.; Jäger, E.; Judson, D.; Khuyagbaatar, J.; Kindler, B.; Kojouharov, I.; Kratz, J. V.; Krier, J.; Kurz, N.; Lens, L.; Ljungberg, J.; Lommel, B.; Louko, J.; Meyer, C.-C.; Mistry, A.; Mokry, C.; Papadakis, P.; Parr, E.; Pore, J. L.; Ragnarsson, I.; Runke, J.; Schädel, M.; Schaffner, H.; Schausten, B.; Shaughnessy, D. A.; Thörle-Pospiech, P.; Trautmann, N.; Uusitalo, J. in Phys. Rev. Lett. (2021). 126(3) 032503.
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First beta-decay spectroscopy of 135In and new beta-decay branches of 134In. Piersa-Si\l{}kowska, M.; Korgul, A.; Benito, J.; Fraile, L. M.; Adamska, E.; Andreyev, A. N.; Álvarez-Rodr\'{i}guez, R.; Barzakh, A. E.; Benzoni, G.; Berry, T.; Borge, M. J. G.; Carmona, M.; Chrysalidis, K.; Correia, J. G.; Costache, C.; Cubiss, J. G.; Day Goodacre, T.; De Witte, H.; Fedorov, D. V.; Fedosseev, V. N.; Fernández-Mart\'{i}nez, G.; Fija\l{}kowska, A.; Fynbo, H.; Galaviz, D.; Galve, P.; Garc\'{\i}a-D\'{i}ez, M.; Greenlees, P. T.; Grzywacz, R.; Harkness-Brennan, L. J.; Henrich, C.; Huyse, M.; Ibá nez, P.; Illana, A.; Janas, Z.; Johnston, K.; Jolie, J.; Judson, D. S.; Karanyonchev, V.; Kiciifmmode \acute{n}else {{\'n}}\fi{}ska Habior, M.; Konki, J.; Koszuk, \L{}.; Kurcewicz, J.; Lazarus, I.; Licifmmode \u{a}else \u{a}\fi{}, R.; López-Montes, A.; Mach, H.; Madurga, M.; Marroqu\'{i}n, I.; Marsh, B.; Mart\'{i}nez, M. C.; Mazzocchi, C.; Miernik, K.; Mihai, C.; Mifmmode \u{a}else \u{a}\fi{}rginean, N.; Mifmmode \u{a}else \u{a}\fi{}rginean, R.; Negret, A.; Nácher, E.; Ojala, J.; Olaizola, B.; Page, R. D.; Pakarinen, J.; Pascu, S.; Paulauskas, S. V.; Perea, A.; Pucknell, V.; Rahkila, P.; Raison, C.; Rapisarda, E.; Rezynkina, K.; Rotaru, F.; Rothe, S.; Rykaczewski, K. P.; Régis, J.-M.; Schomacker, K.; Si\l{}kowski, M.; Simpson, G.; Sotty, C.; Stan, L.; Stifmmode \u{a}else \u{a}\fi{}noiu, M.; Stryjczyk, M.; Sánchez-Parcerisa, D.; Sánchez-Tembleque, V.; Tengblad, O.; Turturicifmmode \u{a}else \u{a}\fi{}, A.; Ud\'{i}as, J. M.; Van Duppen, P.; Vedia, V.; Villa, A.; Vi nals, S.; Wadsworth, R.; Walters, W. B.; Warr, N.; Wilkins, S. G. in Phys. Rev. C (2021). 104(4) 044328.
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First lifetime investigations of N > 82 iodine isotopes: The quest for collectivity. Häfner, G.; Lozeva, R.; Na\"{i}dja, H.; Lebois, M.; Jovancevic, N.; Thisse, D.; Etasse, D.; Canavan, R. L.; Rudigier, M.; Wilson, J. N.; Adamska, E.; Adsley, P.; Algora, A.; Babo, M.; Belvedere, K.; Benito, J.; Benzoni, G.; Blazhev, A.; Boso, A.; Bottoni, S.; Bunce, M.; Chakma, R.; Cieplicka-Oryifmmode \acute{n}else {{\'n}}\fi{}czak, N.; Collins, S. M.; Cortés, M. L.; Davies, P. J.; Delafosse, C.; Fallot, M.; Fraile, L. M.; Gerst, R.-B.; Gjestvang, D.; Guadilla, V.; Hauschild, K.; Henrich, C.; Homm, I.; Ibrahim, F.; Iskra, \L{}. W.; Jazwari, S.; Korgul, A.; Koseoglou, P.; Kröll, Th.; Kurtukian-Nieto, T.; Le meur, L.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Matthieu, L.; Miernik, K.; Nemer, J.; Oberstedt, S.; Paulsen, W.; Piersa-Si\l{}kowska, M.; Popovitch, Y.; Porzio, C.; Qi, L.; Ralet, D.; Regan, P. H.; Reygadas Tello, D.; Rezynkina, K.; Sanchez-Tembleque, V.; Schmitt, C.; Söderström, P.-A.; Sürder, C.; Tocabens, G.; Vedia, V.; Verney, D.; Warr, N.; Wasilewska, B.; Wiederhold, J.; Yavahchova, M. S.; Zeiser, F.; Ziliani, S. in Phys. Rev. C (2021). 104(1) 014316.
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New beta-decaying state in 214Bi. Andel, B.; Van Duppen, P.; Andreyev, A. N.; Blazhev, A.; Grawe, H.; Lica, R.; Naidja, H.; Stryjczyk, M.; Algora, A.; Antalic, S.; Barzakh, A.; Benito, J.; Benzoni, G.; Berry, T.; Borge, M. J. G.; Chrysalidis, K.; Clisu, C.; Costache, C.; Cubiss, J. G.; De Witte, H.; Fedorov, D. V.; Fedosseev, V. N.; Fraile, L. M.; Fynbo, H. O. U.; Greenlees, P. T.; Harkness-Brennan, L. J.; Huyse, M.; Illana, A.; Jolie, J.; Judson, D. S.; Konki, J.; Lazarus, I.; Madurga, M.; Marginean, N.; Marginean, R.; Mihai, C.; Marsh, B. A.; Molkanov, P.; Mosat, P.; Murias, J. R.; Nacher, E.; Negret, A.; Page, R. D.; Pascu, S.; Perea, A.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Rezynkina, K.; Sánchez-Tembleque, V.; Schomacker, K.; Seliverstov, M. D.; Sotty, C.; Stan, L.; Sürder, C.; Tengblad, O.; Vedia, V.; Vinals, S.; Wadsworth, R.; Warr, N. in Phys. Rev. C (2021). 104(5) 054301.
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Enhanced quadrupole collectivity in doubly-magic ⁵⁶Ni: Lifetime measurements of the 4₁⁺ and 6₁⁺ states. Arnswald, K.; Blazhev, A.; Nowacki, F.; Petkov, P.; Reiter, P.; Braunroth, T.; Dewald, A.; Droste, M.; Fransen, C.; Hirsch, R.; Karayonchev, V.; Kaya, L.; Lewandowski, L.; Müller-Gatermann, C.; Seidlitz, M.; Siebeck, B.; Vogt, A.; Werner, D.; Zell, K.O. in Phys. Lett. B (2021). 820 136592.
Lifetime measurements of excited states in doubly-magic 56Ni have been performed exploiting the Doppler-shift attenuation method in order to determine reduced transition probabilities. For the 41+ and 61+ states, the deduced B(E2) values are compared with results from shell-model calculations employing the GXPF1A and the modern PFSDG-U interactions. In addition, valence ab-initio calculations were performed using a novel realistic Hamiltonian derived from chiral perturbation theory including three-body potential contributions and are confronted with the experimental findings. The new results show maximum E2 strength in comparison with known values along the N=28 chain of isotones. The results corroborate the high collectivity for the double shell closure at N=Z=28 which was anticipated from the large B(E2;21+→0g.s.+) value despite the considerable increase of its excitation energy as compared to neighboring semi-magic nuclei. Based on similarities in the shell structures of the self-conjugate doubly-magic nuclei 56Ni and 100Sn, the new values could be an indication for an expected comparable collective behavior of the 61+ state in 100Sn.
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Lifetime measurements of excited states in ⁵⁵Cr. Kleis, H.; Seidlitz, M.; Blazhev, A.; Kaya, L.; Reiter, P.; Arnswald, K.; Dewald, A.; Droste, M.; Fransen, C.; Möller, O.; Shimizu, N.; Tsunoda, Y.; Utsuno, Y.; von Brentano, P.; Zell, K. O. in Phys. Rev. C (2021). 104(3) 034310.
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Spectroscopy and lifetime measurements in ¹³⁴,¹³⁶,¹³⁸Te isotopes and implications for the nuclear structure beyond N=82. Häfner, G.; Lozeva, R.; Naidja, H.; Lebois, M.; Jovancevic, N.; Thisse, D.; Etasse, D.; Canavan, R. L.; Rudigier, M.; Wilson, J. N.; Adamska, E.; Adsley, P.; Babo, M.; Belvedere, K.; Benito, J.; Benzoni, G.; Blazhev, A.; Boso, A.; Bottoni, S.; Bunce, M.; Chakma, R.; Cieplicka-Orynczak, N.; Collins, S. M.; Cortés, M. L.; Davies, P. J.; Delafosse, C.; Fallot, M.; Fornal, B.; Fraile, L. M.; Gerst, R.-B.; Gjestvang, D.; Guadilla, V.; Hauschild, K.; Henrich, C.; Homm, I.; Ibrahim, F.; Iskra, L. W.; Jazwari, S.; Jolie, J.; Korgul, A.; Koseoglou, P.; Kröll, Th.; Kurtukian-Nieto, T.; Le meur, L.; Ljungvall, J.; Lopez-Martens, A.; Matea, I.; Matthieu, L.; Miernik, K.; Nemer, J.; Oberstedt, S.; Paulsen, W.; Piersa, M.; Popovitch, Y.; Porzio, C.; Qi, L.; Ralet, D.; Regan, P. H.; Reygadas Tello, D.; Rezynkina, K.; Sanchez, V.; Schmitt, C.; Söderström, P.-A.; Sürder, C.; Tocabens, G.; Vedia, V.; Verney, D.; Warr, N.; Wasilewska, B.; Wiederhold, J.; Yavahchova, M. S.; Zeiser, F.; Ziliani, S. in Phys. Rev. C (2021). 103(3) 034317.
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Lifetimes and structures of low-lying negative-parity states of 209Po. Karayonchev, V.; Stoyanova, M.; Rainovski, G.; Jolie, J.; Blazhev, A.; Djongolov, M.; Esmaylzadeh, A.; Fransen, C.; Gladnishki, K.; Knafla, L.; Kocheva, D.; Kornwebel, L.; Régis, J.-M.; De Gregorio, G.; Gargano, A. in Phys. Rev. C (2021). 103(4) 044309.
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Angular momentum generation in nuclear fission. Wilson, J. N.; Thisse, D.; Lebois, M.; Jovančević, N.; Gjestvang, D.; Canavan, R.; Rudigier, M.; Étasse, D.; Gerst, R-B; Gaudefroy, L.; Adamska, E.; Adsley, P.; Algora, A.; Babo, M.; Belvedere, K.; Benito, J.; Benzoni, G.; Blazhev, A.; Boso, A.; Bottoni, S.; Bunce, M.; Chakma, R.; Cieplicka-Oryńczak, N.; Courtin, S.; Cortés, M. L.; Davies, P.; Delafosse, C.; Fallot, M.; Fornal, B.; Fraile, L.; Gottardo, A.; Guadilla, V.; Häfner, G.; Hauschild, K.; Heine, M.; Henrich, C.; Homm, I.; Ibrahim, F.; Iskra, Ł. W.; Ivanov, P.; Jazrawi, S.; Korgul, A.; Koseoglou, P.; Kröll, T.; Kurtukian-Nieto, T.; Le Meur, L.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Lozeva, R.; Matea, I.; Miernik, K.; Nemer, J.; Oberstedt, S.; Paulsen, W.; Piersa, M.; Popovitch, Y.; Porzio, C.; Qi, L.; Ralet, D.; Regan, P. H.; Rezynkina, K.; Sánchez-Tembleque, V.; Siem, S.; Schmitt, C.; Söderström, P.-A; Sürder, C.; Tocabens, G.; Vedia, V.; Verney, D.; Warr, N.; Wasilewska, B.; Wiederhold, J.; Yavahchova, M.; Zeiser, F.; Ziliani, S. in Nature (2021). 590(7847) 566--570.
When a heavy atomic nucleus splits (fission), the resulting fragments are observed to emerge spinning1; this phenomenon has been a mystery in nuclear physics for over 40 years2,3. The internal generation of typically six or seven units of angular momentum in each fragment is particularly puzzling for systems that start with zero, or almost zero, spin. There are currently no experimental observations that enable decisive discrimination between the many competing theories for the mechanism that generates the angular momentum4–12. Nevertheless, the consensus is that excitation of collective vibrational modes generates the intrinsic spin before the nucleus splits (pre-scission). Here we show that there is no significant correlation between the spins of the fragment partners, which leads us to conclude that angular momentum in fission is actually generated after the nucleus splits (post-scission). We present comprehensive data showing that the average spin is strongly mass-dependent, varying in saw-tooth distributions. We observe no notable dependence of fragment spin on the mass or charge of the partner nucleus, confirming the uncorrelated post-scission nature of the spin mechanism. To explain these observations, we propose that the collective motion of nucleons in the ruptured neck of the fissioning system generates two independent torques, analogous to the snapping of an elastic band. A parameterization based on occupation of angular momentum states according to statistical theory describes the full range of experimental data well. This insight into the role of spin in nuclear fission is not only important for the fundamental understanding and theoretical description of fission, but also has consequences for the γ-ray heating problem in nuclear reactors13,14, for the study of the structure of neutron-rich isotopes15,16, and for the synthesis and stability of super-heavy elements17,18.
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Lifetimes and structures of low-lying negative-parity states of 209Po. Karayonchev, V.; Stoyanova, M.; Rainovski, G.; Jolie, J.; Blazhev, A.; Djongolov, M.; Esmaylzadeh, A.; Fransen, C.; Gladnishki, K.; Knafla, L.; Kocheva, D.; Kornwebel, L.; Régis, J.-M.; De Gregorio, G.; Gargano, A. in Phys. Rev. C (2021). 103(4) 044309.
The 5/2−1, 9/2−1, and 11/2−1 states in 209Po were populated in the β decay of 209At and their lifetimes measured using the electronic γ−γ fast timing technique. The lifetime of the 9/2−1 state is measured for first time. The lifetime of the 5/2−1 is measured to be shorter than the value adopted in the literature while the lifetime of the 11/2−1 state agrees well with the previous measurement. In order to get deeper insight into the structure of the states, a shell-model calculation was carried out adopting a microscopic effective interaction derived from the realistic CD-Bonn potential. The comparison between theoretical and experimental data for the low-lying negative-parity states of 209Po supports the reliability of the predicted wave functions, which are found to be dominated by the coupling of a neutron hole to the yrast states of 210Po. However, it also points to the important role played by minor wave-function components in describing the reduced electromagnetic strengths, suggesting the need of additional configuration mixing for achieving a better quantitative agreement.
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γ-ray Spectroscopy of 85Se Produced in 232Th Fission. Adamska, E.; Korgul, A.; Fijałkowska, A.; Miernik, K.; Piersa, A.; Canavan, R.; Etasse, D.; Jovančević, N.; Lebois, M.; Rudigier, M.; Thisse, D.; Wilson, J.N.; Adsley, P.; Algora, A.; Babo, M.; Belvedere, K.; Benito, J.; Blazhev, A.; Benzoni, G.; Boso, A.; Bottoni, S.; Bunce, M.; Chakma, R.; Cieplicka-Oryńczak, N.; Ciemała, M.; Collins, S.; Cortés, L.; Davies, P.; Delafosse, C.; Fallot, M.; Fornal, B.; Fraile, L.M.; Gerst, R.-B.; Gjestvang, D.; Gottardo, A.; Guadilla, V.; Hafner, G.; Hauschild, K.; Heine, M.; Henrich, C.; Homm, I.; Ibrahim, F.; Iskra, Ł.W.; Koseoglou, P.; Kröll, T.; Kurtukian-Nieto, T.; Le meur, L.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Lozeva, R.; Matea, I.; Nemer, J.; Oberstedt, S.; Paulsen, W.; Popovitch, Y.; Qi, L.; Ralet, D.; Regan, P.H.; Reygadas Tello, D.; Rezynkina, K.; Sánchez-Tembleque, V.; Schmitt, C.; Söderström, P.-A.; Surder, C.; Tocabens, G.; Vedia, V.; Verney, D.; Warr, N.; Wasilewska, B.; Wiederhold, J.; Yavahchova, M.; Zeiser, F. in Acta. Phys. Pol. (2020). B 51 843-848.
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Experimental evidence for low-lying quadrupole isovector excitation of 208Po. Yaneva, A.; Kocheva, D.; Rainovski, G.; Jolie, J.; Pietralla, N.; Blazhev, A.; Dewald, A.; Djongolov, M.; Fransen, C.; Gladnishki, K. A.; Henrich, C.; Homm, I.; Ide, K. E.; John, P. R.; Kalaydjieva, D.; Karayonchev, V.; Kern, R.; Kleemann, J.; Kröll, Th.; Müller-Gatermann, C.; Scheck, M.; Spagnoletti, P.; Stoyanova, M.; Werner, V. in The European Physical Journal A (2020). 56(246) 7.
We present the results from an experiment dedicated to measure the lifetime of the 22+ state, candidate for the one-phonon mixed-symmetry state, of 208Po. This nucleus was studied in the α-transfer reaction 204Pb(12C,8Be)208Po and the lifetime of the 22+ state was determined by utilizing the Doppler-shift attenuation method. The experimental data show that the 22+ state decays with a sizable M1 transition to the 21+ state revealing its isovector nature.
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Fast-timing study of 81Ga from the β decay of 81Zn. Paziy, V.; Fraile, L. M.; Mach, H.; Olaizola, B.; Simpson, G. S.; Aprahamian, A.; Bernards, C.; Briz, J. A.; Bucher, B.; Chiara, C. J.; Dlouhý, Z.; Gheorghe, I.; Ghiţǎ, D.; Hoff, P.; Jolie, J.; Köster, U.; Kurcewicz, W.; Licǎ, R.; Mǎrginean, N.; Mǎrginean, R.; Régis, J. M.; Rudigier, M.; Sava, T.; Stǎnoiu, M.; Stroe, L.; Walters, W. B. in Phys. Rev. C (2020). 102(1) 014329.
The β− decay of 81Zn to the neutron magic N = 50 nucleus 81Ga, with only three valence protons with respect to 78Ni, was investigated. The study was performed at the ISOLDE facility at CERN by means of γ spectroscopy. The 81Zn half-life was determined to be T1/2 = 290(4) ms while the β-delayed neutron emission probability was measured as Pn = 23(4)%. The analysis of the β-gated γ -ray singles and γ -γ coincidences from the decay of 81Zn provides 47 new levels and 70 new transitions in 81Ga. The β−n decay of 81Zn was observed and a new decay scheme into the odd-odd 80Ga nucleus was established. The half-lives of the first and second excited states of 81Ga were measured via the fast-timing method using LaBr3(Ce) detectors. The level scheme and transition rates are compared to large-scale shell-model calculations. The low-lying structure of 81Ga is interpreted in terms of the coupling of the three valence protons outside the doubly magic 78Ni core.
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FATIMA — FAst TIMing Array for DESPEC at FAIR. Rudigier, M.; Podolyák, Zs.; Regan, P.H.; Bruce, A.M.; Lalkovski, S.; Canavan, R.L.; Gamba, E.R.; Roberts, O.; Burrows, I.; Cullen, D.M.; Fraile, L.M.; Gerhard, L.; Gerl, J.; Gorska, M.; Grant, A.; Jolie, J.; Karayonchev, V.; Kurz, N.; Korten, W.; Lazarus, I.H.; Nita, C.R.; Pucknell, V.F.E.; Régis, J.-M.; Schaffner, H.; Simpson, J.; Singh, P.; Townsley, C.M.; Smith, J.F.; Vesic, J. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2020). 969 163967.
The components, working principle and characteristics of FATIMA (FAst TIMing Array), a fast-timing detector system for DESPEC at FAIR, are described. The core system includes 36 LaBr3(Ce) scintillator detectors, a mounting frame for the DESPEC station and a VME-based fast-timing data acquisition system. The current electronic timing circuit is based on V812 constant fraction discriminators and V1290 time-to-digital converters. Gamma-ray energies are measured using V1751 digitisers. Characteristics of the core FATIMA system including efficiency, energy, and coincidence resolving time, as well as limitations, are discussed on the basis of test measurements performed in the S4 cave at GSI, Germany. The coincidence γ-γ time resolution for the prompt 60Co cascade is determined to be ∼320 ps full width at half maximum. The total full energy peak efficiency at 1 MeV for the 36 detector array in the DESPEC setup is 2.9%. The energy-dependent prompt response centroid curve with the current CFD/TDC combination is shown to be smooth; the centroid shift method can be applied for the measurement of half-lives below 200 ps. An overview of applications of the FATIMA detectors as an ancilliary system in combination with other detector arrays during recent years is given. Data on the operation of the detectors in the presence of magnetic fields are presented.
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Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus ⁸⁸Ru. Cederwall, B.; Liu, X.; Aktas, Ö.; Ertoprak, A.; Zhang, W.; Qi, C.; Clément, E.; de France, G.; Ralet, D.; Gadea, A.; Goasduff, A.; Jaworski, G.; Kuti, I.; Nyakó, B. M.; Nyberg, J.; Palacz, M.; Wadsworth, R.; Valiente-Dobón, J. J.; Al-Azri, H.; Ataç Nyberg, A.; Bäck, T.; de Angelis, G.; Doncel, M.; Dudouet, J.; Gottardo, A.; Jurado, M.; Ljungvall, J.; Mengoni, D.; Napoli, D. R.; Petrache, C. M.; Sohler, D.; Timár, J.; Barrientos, D.; Bednarczyk, P.; Benzoni, G.; Birkenbach, B.; Boston, A. J.; Boston, H. C.; Burrows, I.; Charles, L.; Ciemala, M.; Crespi, F. C. L.; Cullen, D. M.; Désesquelles, P.; Domingo-Pardo, C.; Eberth, J.; Erduran, N.; Ertürk, S.; González, V.; Goupil, J.; Hess, H.; Huyuk, T.; Jungclaus, A.; Korten, W.; Lemasson, A.; Leoni, S.; Maj, A.; Menegazzo, R.; Million, B.; Perez-Vidal, R. M.; Podolyak, Zs.; Pullia, A.; Recchia, F.; Reiter, P.; Saillant, F.; Salsac, M. D.; Sanchis, E.; Simpson, J.; Stezowski, O.; Theisen, Ch.; Zielińska, M. in Phys. Rev. Lett. (2020). 124(6) 062501.
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Testing ab initio nuclear structure in neutron-rich nuclei: Lifetime measurements of second 2⁺ state in ¹⁶C and ²⁰O. Ciemała, M.; Ziliani, S.; Crespi, F. C. L.; Leoni, S.; Fornal, B.; Maj, A.; Bednarczyk, P.; Benzoni, G.; Bracco, A.; Boiano, C.; Bottoni, S.; Brambilla, S.; Bast, M.; Beckers, M.; Braunroth, T.; Camera, F.; Cieplicka-Oryńczak, N.; Clément, E.; Coelli, S.; Dorvaux, O.; Erturk, S.; de France, G.; Fransen, C.; Goldkuhle, A.; Grębosz, J.; Harakeh, M. N.; Iskra, Ł. W.; Jacquot, B.; Karpov, A.; Kicińska Habior, M.; Kim, Y.; Kmiecik, M.; Lemasson, A.; Lenzi, S. M.; Lewitowicz, M.; Li, H.; Matea, I.; Mazurek, K.; Michelagnoli, C.; Matejska-Minda, M.; Million, B.; Müller-Gatermann, C.; Nanal, V.; Napiorkowski, P.; Napoli, D. R.; Palit, R.; Rejmund, M.; Schmitt, Ch.; Stanoiu, M.; Stefan, I.; Vardaci, E.; Wasilewska, B.; Wieland, O.; Zieblinski, M.; Zielińska, M.; Ataç, A.; Barrientos, D.; Birkenbach, B.; Boston, A. J.; Cederwall, B.; Charles, L.; Collado, J.; Cullen, D. M.; Désesquelles, P.; Domingo-Pardo, C.; Dudouet, J.; Eberth, J.; González, V.; Goupil, J.; Harkness-Brennan, L. J.; Hess, H.; Judson, D. S.; Jungclaus, A.; Korten, W.; Labiche, M.; Lefevre, A.; Menegazzo, R.; Mengoni, D.; Nyberg, J.; Perez-Vidal, R. M.; Podolyak, Zs.; Pullia, A.; Recchia, F.; Reiter, P.; Saillant, F.; Salsac, M. D.; Sanchis, E.; Stezowski, O.; Theisen, Ch.; Valiente-Dobón, J. J.; Holt, J. D.; Menéndez, J.; Schwenk, A.; Simonis, J. in Phys. Rev. C (2020). 101(2) 021303.
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Quadrupole deformation of 130Xe measured in a Coulomb-excitation experiment. Morrison, L.; Hadyńska-Klȩk, K.; Podolyák, Zs.; Doherty, D. T.; Gaffney, L. P.; Kaya, L.; Próchniak, L.; Samorajczyk-Pyśk, J.; Srebrny, J.; Berry, T.; Boukhari, A.; Brunet, M.; Canavan, R.; Catherall, R.; Colosimo, S. J.; Cubiss, J. G.; De Witte, H.; Fransen, Ch.; Giannopoulos, E.; Hess, H.; Kröll, T.; Lalović, N.; Marsh, B.; Palenzuela, Y. Martinez; Napiorkowski, P. J.; O'Neill, G.; Pakarinen, J.; Ramos, J. P.; Reiter, P.; Rodriguez, J. A.; Rosiak, D.; Rothe, S.; Rudigier, M.; Siciliano, M.; Snäll, J.; Spagnoletti, P.; Thiel, S.; Warr, N.; Wenander, F.; Zidarova, R.; Zielińska, M. in Phys. Rev. C (2020). 102(5) 054304.
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Low-lying electric dipole γ-continuum for the unstable 62,64Fe nuclei: Strength evolution with neutron number. Avigo, R.; Wieland, O.; Bracco, A.; Camera, F.; Ameil, F.; Arici, T.; Ataç, A.; Barrientos, D.; Bazzacco, D.; Bednarczyk, P.; Benzoni, G.; Birkenbach, B.; Blasi, N.; Boston, H.C.; Bottoni, S.; Brambilla, S.; Bruyneel, B.; Ciemała, M.; Clément, E.; Cortés, M.L.; Crespi, F.C.L.; Cullen, D.M.; Curien, D.; Didierjean, F.; Domingo-Pardo, C.; Duchêne, G.; Eberth, J.; Görgen, A.; Gadea, A.; Gerl, J.; Goel, N.; Golubev, P.; González, V.; Górska, M.; Gottardo, A.; Gregor, E.; Guastalla, G.; Habermann, T.; Harkness-Brennan, L.J.; Jungclaus, A.; Kmiecik, M.; Kojouharov, I.; Korten, W.; Kurz, N.; Labiche, M.; Lalović, N.; Leoni, S.; Lettmann, M.; Maj, A.; Menegazzo, R.; Mengoni, D.; Merchan, E.; Million, B.; Morales, A.I.; Napoli, D.R.; Nociforo, C.; Nyberg, J.; Pietralla, N.; Pietri, S.; Podolyák, Zs.; Ponomarev, V.Yu.; Pullia, A.; Quintana, B.; Rainovski, G.; Ralet, D.; Recchia, F.; Reese, M.; Regan, P.; Reiter, P.; Riboldi, S.; Rudolph, D.; Salsac, M.D.; Sanchis, E.; Sarmiento, L.G.; Schaffner, H.; Simpson, J.; Stezowski, O.; Valiente-Dobón, J.J.; Wollersheim, H.J. in Physics Letters B (2020). 811 135951.
The γ-ray emission from the nuclei 62,64Fe following Coulomb excitation at bombarding energy of 400-440 AMeV was measured with special focus on E1 transitions in the energy region 4-8 MeV. The unstable neutron-rich nuclei 62,64Fe were produced at the FAIR-GSI laboratories and selected with the FRS spectrometer. The γ decay was detected with AGATA. From the measured γ-ray spectra the summed E1 strength is extracted and compared to microscopic quasi-particle phonon model calculations. The trend of the E1 strength with increasing neutron number is found to be fairly well reproduced with calculations that assume a rather complex structure of the 1− states (three-phonon states) inducing a strong fragmentation of the E1 nuclear response below the neutron binding energy.
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Evolution of collectivity in 118Xe. Müller-Gatermann, C.; Dewald, A.; Fransen, C.; Beckers, M.; Blazhev, A.; Braunroth, T.; Goldkuhle, A.; Jolie, J.; Kornwebel, L.; Reviol, W.; von Spee, F.; Zell, K. O. in Phys. Rev. C (2020). 102(6) 064318.
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Tests of collectivity in 98Zr by absolute transition rates. Karayonchev, V.; Jolie, J.; Blazhev, A.; Dewald, A.; Esmaylzadeh, A.; Fransen, C.; Häfner, G.; Knafla, L.; Litzinger, J.; Müller-Gatermann, C.; Régis, J.-M.; Schomacker, K.; Vogt, A.; Warr, N.; Leviatan, A.; Gavrielov, N. in Phys. Rev. C (2020). 102(6) 064314.
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Prompt and delayed gamma spectroscopy of neutron-rich 94Kr and observation of a new isomer. Gerst, R.-B.; Blazhev, A.; Warr, N.; Wilson, J. N.; Lebois, M.; Jovančević, N.; Thisse, D.; Canavan, R.; Rudigier, M.; Étasse, D.; Adamska, E.; Adsley, P.; Algora, A.; Babo, M.; Belvedere, K.; Benito, J.; Benzoni, G.; Boso, A.; Bottoni, S.; Bunce, M.; Chakma, R.; Cieplicka-Oryńczak, N.; Courtin, S.; Cortés, M. L.; Davies, P.; Delafosse, C.; Fallot, M.; Fornal, B.; Fraile, L. M.; Gjestvang, D.; Gottardo, A.; Guadilla, V.; Häfner, G.; Hauschild, K.; Heine, M.; Henrich, C.; Homm, I.; Ibrahim, F.; Iskra, L. W.; Ivanov, P.; Jazrawi, S.; Korgul, A.; Koseoglou, P.; Kröll, T.; Kurtukian-Nieto, T.; Le Meur, L.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Lozeva, R.; Matea, I.; Miernik, K.; Nemer, J.; Oberstedt, S.; Paulsen, W.; Piersa, M.; Popovitch, Y.; Porzio, C.; Qi, L.; Ralet, D.; Regan, P. H.; Reygadas-Tello, D.; Rezynkina, K.; Sánchez-Tembleque, V.; Schmitt, C.; Söderström, P.-A.; Sürder, C.; Tocabens, G.; Vedia, V.; Verney, D.; Wasilewska, B.; Wiederhold, J.; Yavachova, M.; Zeiser, F.; Ziliani, S. in Phys. Rev. C (2020). 102(6) 064323.
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Lifetime measurements in ⁴⁴Ti. Arnswald, K.; Reiter, P.; Blazhev, A.; Braunroth, T.; Dewald, A.; Droste, M.; Fransen, C.; Goldkuhle, A.; Hetzenegger, R.; Hirsch, R.; Hoemann, E.; Kaya, L.; Lewandowski, L.; Müller-Gatermann, C.; Petkov, P.; Rosiak, D.; Seidlitz, M.; Siebeck, B.; Vogt, A.; Werner, D.; Wolf, K.; Zell, K.-O. in Phys. Rev. C (2020). 102(5) 054302.
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Lifetime measurements of excited states in neutron-rich 53Ti: Benchmarking effective shell-model interactions. Goldkuhle, A.; Blazhev, A.; Fransen, C.; Dewald, A.; Beckers, M.; Birkenbach, B.; Braunroth, T.; Clément, E.; Dudouet, J.; Eberth, J.; Hess, H.; Jacquot, B.; Jolie, J.; Kim, Y.-H.; Lemasson, A.; Lenzi, S. M.; Li, H. J.; Litzinger, J.; Michelagnoli, C.; Müller-Gatermann, C.; Nara Singh, B. S.; Pérez-Vidal, R. M.; Ralet, D.; Reiter, P.; Vogt, A.; Warr, N.; Zell, K. O. in Phys. Rev. C (2020). 102(5) 054334.
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New measurement of the 144Sm(alpha,gamma)148Gd reaction rate for the gamma process. Scholz, P.; Wilsenach, H.; Becker, H. W.; Blazhev, A.; Heim, F.; Foteinou, V.; Giesen, U.; Münker, C.; Rogalla, D.; Sprung, P.; Zilges, A.; Zuber, K. in Phys. Rev. C (2020). 102(4) 045811.
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Restoring the valence-shell stabilization in 140Nd. Kern, R.; Zidarova, R.; Pietralla, N.; Rainovski, G.; Stegmann, R.; Blazhev, A.; Boukhari, A.; Cederkäll, J.; Cubiss, J. G.; Djongolov, M.; Fransen, C.; Gaffney, L. P.; Gladnishki, K.; Giannopoulos, E.; Hess, H.; Jolie, J.; Karayonchev, V.; Kaya, L.; Keatings, J. M.; Kocheva, D.; Kröll, Th.; Möller, O.; O'Neill, G. G.; Pakarinen, J.; Reiter, P.; Rosiak, D.; Scheck, M.; Snall, J.; Söderström, P.-A.; Spagnoletti, P.; Stoyanova, M.; Thiel, S.; Vogt, A.; Warr, N.; Welker, A.; Werner, V.; Wiederhold, J.; De Witte, H. in Phys. Rev. C (2020). 102(4) 041304.
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Competition between Allowed and First-Forbidden Beta Decay: The Case of 208Hg -> 208Tl. Carroll, R. J.; Podolyák, Zs.; Berry, T.; Grawe, H.; Alexander, T.; Andreyev, A. N.; Ansari, S.; Borge, M. J. G.; Brunet, M.; Creswell, J. R.; Fraile, L. M.; Fahlander, C.; Fynbo, H. O. U.; Gamba, E. R.; Gelletly, W.; Gerst, R.-B.; Górska, M.; Gredley, A.; Greenlees, P. T.; Harkness-Brennan, L. J.; Huyse, M.; Judge, S. M.; Judson, D. S.; Konki, J.; Kurcewicz, J.; Kuti, I.; Lalkovski, S.; Lazarus, I. H.; Licifmmode \u{a}else \u{a}\fi{}, R.; Lund, M.; Madurga, M.; Marginean, N.; Marginean, R.; Marroquin, I.; Mihai, C.; Mihai, R. E.; Nácher, E.; Negret, A.; Nita, C.; Pascu, S.; Page, R. D.; Patel, Z.; Perea, A.; Phrompao, J.; Piersa, M.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Regan, P. H.; Rotaru, F.; Rudigier, M.; Shand, C. M.; Shearman, R.; Stegemann, S.; Stora, T.; Sotty, Ch.; Tengblad, O.; Van Duppen, P.; Vedia, V.; Wadsworth, R.; Walker, P. M.; Warr, N.; Wearing, F.; De Witte, H. in Phys. Rev. Lett. (2020). 125(19) 192501.
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Quadrupole deformation of 130Xe measured in a Coulomb-excitation experiment. Morrison, L.; Hadyńska-Klek, K.; Podolyák, Zs.; Doherty, D. T.; Gaffney, L. P.; Kaya, L.; Próchniak, L.; Samorajczyk-Pyśk, J.; Srebrny, J.; Berry, T.; Boukhari, A.; Brunet, M.; Canavan, R.; Catherall, R.; Colosimo, S. J.; Cubiss, J. G.; De Witte, H.; Fransen, Ch.; Giannopoulos, E.; Hess, H.; Kröll, T.; Lalovic, N.; Marsh, B.; Palenzuela, Y. Martinez; Napiorkowski, P. J.; O'Neill, G.; Pakarinen, J.; Ramos, J. P.; Reiter, P.; Rodriguez, J. A.; Rosiak, D.; Rothe, S.; Rudigier, M.; Siciliano, M.; Snäll, J.; Spagnoletti, P.; Thiel, S.; Warr, N.; Wenander, F.; Zidarova, R.; Zielińska, M. in Phys. Rev. C (2020). 102(5) 054304.
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Lifetime measurements in the odd-A nucleus 177Hf. Knafla, L.; Alexa, P.; Köster, U.; Thiamova, G.; Régis, J.-M.; Jolie, J.; Blanc, A.; Bruce, A. M.; Esmaylzadeh, A.; Fraile, L. M.; de France, G.; Häfner, G.; Ilieva, S.; Jentschel, M.; Karayonchev, V.; Korten, W.; Kröll, T.; Lalkovski, S.; Leoni, S.; Mach, H.; Marginean, N.; Mutti, P.; Pascovici, G.; Paziy, V.; Podolyák, Zs.; Regan, P. H.; Roberts, O. J.; Saed-Samii, N.; Simpson, G. S.; Smith, J. F.; Soldner, T.; Townsley, C.; Ur, C. A.; Urban, W.; Vancraeyenest, A.; Warr, N. in Phys. Rev. C (2020). 102(5) 054322.
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Population of lead isotopes in binary reactions using a 94Rb radioactive beam. Čolović, P.; Szilner, S.; Illana, A.; Valiente-Dobón, J. J.; Corradi, L.; Pollarolo, G.; Mijatović, T.; Goasduff, A.; Benzoni, G.; Borge, M. J. G.; Boso, A.; Boukhari, A.; Ceruti, S.; Cubiss, J. G.; de Angelis, G.; De Witte, H.; Fioretto, E.; Fransen, Ch.; Galtarossa, F.; Gaffney, L. P.; Giannopoulos, E.; Hess, H.; Jurado-Gomez, M. L.; Kaya, L.; Kröll, Th.; Marchi, T.; Menegazzo, R.; Mengoni, D.; Napoli, D. R.; O'Neill, G.; Pakarinen, J.; Podolyák, Zs.; Recchia, F.; Reiter, P.; Rosiak, D.; Snall, J.; Spagnoletti, P.; Testov, D.; Thiel, S.; Warr, N.; Zidarova, R. in Phys. Rev. C (2020). 102(5) 054609.
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Sequential Nature of \($(p,3p)$\) Two-Proton Knockout from Neutron-Rich Nuclei. Frotscher, A.; Gómez-Ramos, M.; Obertelli, A.; Doornenbal, P.; Authelet, G.; Baba, H.; Calvet, D.; Château, F.; Chen, S.; Corsi, A.; Delbart, A.; Gheller, J.-M.; Giganon, A.; Gillibert, A.; Isobe, T.; Lapoux, V.; Matsushita, M.; Momiyama, S.; Motobayashi, T.; Niikura, M.; Otsu, H.; Paul, N.; Péron, C.; Peyaud, A.; Pollacco, E. C.; Roussé, J.-Y.; Sakurai, H.; Santamaria, C.; Sasano, M.; Shiga, Y.; Shimizu, N.; Steppenbeck, D.; Takeuchi, S.; Taniuchi, R.; Uesaka, T.; Wang, H.; Yoneda, K.; Ando, T.; Arici, T.; Blazhev, A.; Browne, F.; Bruce, A. M.; Carroll, R.; Chung, L. X.; Cortés, M. L.; Dewald, M.; Ding, B.; Dombradi, Zs.; Flavigny, F.; Franchoo, S.; Giacoppo, F.; Górska, M.; Gottardo, A.; Hadyifmmode \acute{n}else {{\'n}}\fi{}ska-Klifmmode \mbox{\k{e}}else \k{e}\fi{}k, K.; Korkulu, Z.; Koyama, S.; Kubota, Y.; Jungclaus, A.; Lee, J.; Lettmann, M.; Linh, B. D.; Liu, J.; Liu, Z.; Lizarazo, C.; Louchart, C.; Lozeva, R.; Matsui, K.; Miyazaki, T.; Moschner, K.; Nagamine, S.; Nakatsuka, N.; Nita, C.; Nishimura, S.; Nobs, C. R.; Olivier, L.; Ota, S.; Patel, Z.; Podolyák, Zs.; Rudigier, M.; Sahin, E.; Saito, T. Y.; Shand, C.; Söderström, P.-A.; Stefan, I. G.; Sumikama, T.; Suzuki, D.; Orlandi, R.; Vaquero, V.; Vajta, Zs.; Werner, V.; Wimmer, K.; Wu, J.; Xu, Z. in Phys. Rev. Lett. (2020). 125(1) 012501.
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Decay studies of the long-lived states in \($^{186}\mathrm{Tl}$\). Stryjczyk, M.; Andel, B.; Andreyev, A. N.; Cubiss, J.; Pakarinen, J.; Rezynkina, K.; Van Duppen, P.; Antalic, S.; Berry, T.; Borge, M. J. G.; Clisu, C.; Cox, D. M.; De Witte, H.; Fraile, L. M.; Fynbo, H. O. U.; Gaffney, L. P.; Harkness-Brennan, L. J.; Huyse, M.; Illana, A.; Judson, D. S.; Konki, J.; Kurcewicz, J.; Lazarus, I.; Lica, R.; Madurga, M.; Marginean, N.; Marginean, R.; Mihai, C.; Mosat, P.; Nacher, E.; Negret, A.; Ojala, J.; Ovejas, J. D.; Page, R. D.; Papadakis, P.; Pascu, S.; Perea, A.; Podolyák, Zs.; Pucknell, V.; Rapisarda, E.; Rotaru, F.; Sotty, C.; Tengblad, O.; Vedia, V.; Vi nals, S.; Wadsworth, R.; Warr, N.; Wrzosek-Lipska, K. in Phys. Rev. C (2020). 102(2) 024322.
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Benchmarking the PreSPEC@GSI experiment for Coulex-multipolarimetry on the π(p3/2) --> π(p1/2) spin-flip transition in 85Br. Napiralla, P.; Lettmann, M.; Stahl, C.; Rainovski, G.; Pietralla, N.; Afara, S.; Ameil, F.; Arici, T.; Aydin, S.; Barrientos, D.; Bednarczyk, P.; Bentley, M. A.; Benzoni, G.; Birkenbach, B.; Blazhev, A.; Boston, A. J.; Boutachkov, P.; Bracco, A.; Bruyneel, B.; Cl{é}ment, E.; Cort{é}s, M. L.; Crespi, F. C. L.; Cullen, D. M.; Curien, D.; D{é}sesquelles, P.; Didierjean, F.; Domingo-Pardo, C.; Duch{ê}ne, G.; Eberth, J.; Egger, H.; Fahlander, C.; Gerl, J.; Gladnishki, K. A.; Golubev, P.; Gonz{á}lez, V.; G{ó}rska, M.; Gottardo, A.; Grassi, L.; Habermann, T.; Harkness-Brennan, L. J.; Hess, H.; Jenkins, D. G.; John, P. R.; Jolie, J.; Judson, D. S.; Kojouharov, I.; Korten, W.; Labiche, M.; Lalovi{{{'c}}}, N.; Lizarazo, C.; Louchart-Henning, C.; Maj, A.; Menegazzo, R.; Mengoni, D.; Merchan, E.; Million, B.; M{ö}ller, O.; M{ö}ller, T.; Moschner, K.; Modamio, V.; Napoli, D.; Singh, B. S. Nara; Podoly{á}k, Zs.; Pietri, S.; Ralet, D.; Reese, M.; Reiter, P.; Rudolph, D.; Sanchis, E.; Sarmiento, L. G.; Schaffner, H.; Simpson, J.; Singh, P. P.; Valiente-Dob{ó}n, J. J.; Werner, V.; Wieland, O. in The European Physical Journal A (2020). 56(5) 147.
A first performance test of the Coulomb excitation multipolarimetry (Coulex-multipolarimetry) method is presented. It is based on a {\\($}{\$\)}^{\{}85{\}}{backslash}hbox {\{}Br{\}}{\backslash},{backslash}pi p{\_}{\{}3/2{\}}{backslash}rightarrow {backslash}pi p{\_}{\{}1/2{\}}{\\($}{\$\)}85Br\($\pi$\)p3/2{\textrightarrow}\($\pi$\)p1/2 spin-flip experiment performed as part of the PreSPEC-AGATA campaign at the GSI Helmholtzzentrum f{ü}r Schwerionenforschung (GSI). Via determination of background levels around the expected {\\($}{\$\)}^{\{}85{\}}{backslash}hbox {\{}Br{\}}{\\($}{\$\)}85Br excitations as well as measured {\\($}{\$\)}^{\{}197{\}}{backslash}hbox {\{}Au{\}}{\\($}{\$\)}197Au excitations, an upper limit for the M1 transition strength of the {\\($}{\$\)}1/2{\_}1^-{backslash}rightarrow 3/2{\_}{backslash}text {\{}g.s.{\}}^-{\\($}{\$\)}1/21-{textrightarrow}3/2g.s.- transition in {\\($}{\$\)}^{\{}85{\}}{backslash}hbox {\{}Br{\}}{\\($}{\$\)}85Br and a lower beam time limit for upcoming experimental campaigns utilizing Coulex-multipolarimetry have been inferred. The impact of the use of AGATA in its anticipated {\\($}{\$\)}1{backslash}pi {\\($}{\$\)}1\($\pi$\) configuration on these estimates is deduced via Geant4 simulations.
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Nuclear structure studies with re-accelerated beams at REX-and HIE-ISOLDE. Reiter, P.; Warr, N. in Progress in Particle and Nuclear Physics (2020). 113 103767.
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Compex: a cubic germanium detector. Såmark-Roth, A.; Cox, D. M.; Eberth, J.; Golubev, P.; Rudolph, D.; Sarmiento, L. G.; Tocabens, G.; Ginsz, M.; Pirard, B.; Quirin, P. in The European Physical Journal A (2020). 56(5) 141.
The Compex detector is an electrically cooled, composite germanium detector that uses four coaxial, cubic-shaped, single-encapsulated germanium crystals. This novel detector allows for new heights in photon detection efficiency in decay spectroscopy setups using box-shaped vacuum chambers. Its spectroscopic performance and detection efficiency is evaluated by means of source measurements. Motivated by Compex's unique cubic germanium crystals, the Lund scanning system has been developed. The constructed system is used to characterise the response as a function of interaction position within a Compex crystal. Sensitivity across the front face, pulse shapes, and rise times have been analysed. Future development and applications of the Compex detector are discussed.
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Pairing-quadrupole interplay in the neutron-deficient tin nuclei: First lifetime measurements of low-lying states in 106,108Sn. Siciliano, M.; Valiente-Dobón, J.J; Goasduff, A.; Nowacki, F.; Zuker, A.P; Bazzacco, D.; Lopez-Martens, A.; Clément, E.; Benzoni, G.; Braunroth, T.; Crespi, F.C.L; Cieplicka-Oryńczak, N.; Doncel, M.; Ertürk, S.; de France, G.; Fransen, C.; Gadea, A.; Georgiev, G.; Goldkuhle, A.; Jakobsson, U.; Jaworski, G.; John, P.R; Kuti, I.; Lemasson, A.; Marchi, T.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Müller-Gatermann, C.; Napoli, D.R; Nyberg, J.; Palacz, M.; Pérez-Vidal, R.M; Sayği, B.; Sohler, D.; Szilner, S.; Testov, D.; Zielińska, M.; Barrientos, D.; Birkenbach, B.; Boston, H.C; Boston, A.J; Cederwall, B.; Collado, J.; Cullen, D.M; Désesquelles, P.; Domingo-Pardo, C.; Dudouet, J.; Eberth, J.; Egea-Canet, F.J; González, V.; Harkness-Brennan, L.J; Hess, H.; Judson, D.S; Jungclaus, A.; Korten, W.; Labiche, M.; Lefevre, A.; Leoni, S.; Li, H.; Maj, A.; Menegazzo, R.; Million, B.; Pullia, A.; Recchia, F.; Reiter, P.; Salsac, M.D; Sanchis, E.; Stezowski, O.; Theisen, Ch in Physics Letters B (2020). 806 135474--.
The lifetimes of the low-lying excited states 2+ and 4+ have been directly measured in the neutron-deficient 106,108Sn isotopes. The nuclei were populated via a deep-inelastic reaction and the lifetime measurement was performed employing a differential plunger device. The emitted γ rays were detected by the AGATA array, while the reaction products were uniquely identified by the VAMOS++ magnetic spectrometer. Large-Scale Shell-Model calculations with realistic forces indicate that, independently of the pairing content of the interaction, the quadrupole force is dominant in the B(E2;21+→0g.s.+) values and it describes well the experimental pattern for 104−114Sn; the B(E2;41+→21+) values, measured here for the first time, depend critically on a delicate pairing-quadrupole balance, disclosed by the very precise results in 108Sn.
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Physics opportunities with the Advanced Gamma Tracking Array: AGATA. Korten, W.; Atac, A.; Beaumel, D.; Bednarczyk, P.; Bentley, M. A.; Benzoni, G.; Boston, A.; Bracco, A.; Cederkäll, J.; Cederwall, B.; Ciemała, M.; Clément, E.; Crespi, F. C. L.; Curien, D.; de Angelis, G.; Didierjean, F.; Doherty, D. T.; Dombradi, Zs; Duchêne, G.; Dudek, J.; Fernandez-Dominguez, B.; Fornal, B.; Gadea, A.; Gaffney, L. P.; Gerl, J.; Gladnishki, K.; Goasduff, A.; Górska, M.; Greenlees, P. T.; Hess, H.; Jenkins, D. G.; John, P. R.; Jungclaus, A.; Kmiecik, M.; Korichi, A.; Labiche, M.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Maj, A.; Mengoni, D.; Million, B.; Nannini, A.; Napoli, D.; Nolan, P. J.; Nyberg, J.; Obertelli, A.; Pakarinen, J.; Pietralla, N.; Podolyák, Zs; Quintana, B.; Raabe, R.; Rainovski, G.; Recchia, F.; Reiter, P.; Rudolph, D.; Simpson, J.; Theisen, Ch; Tonev, D.; Tumino, A.; Valiente-Dobón, J. J.; Wieland, O.; Wimmer, K.; Zielińska, M.; Collaboration, the AGATA in The European Physical Journal A (2020). 56(5) 137--.
New physics opportunities are opening up by the Advanced Gamma Tracking Array, AGATA, as it evolves to the full 4\($$\)pi \($$\)π instrument. AGATA is a high-resolution \($$\)gamma \($$\)γ-ray spectrometer, solely built from highly segmented high-purity Ge detectors, capable of measuring \($$\)gamma \($$\)γ rays from a few tens of keV to beyond 10 MeV, with unprecedented efficiency, excellent position resolution for individual \($$\)gamma \($$\)γ-ray interactions, and very high count-rate capability. As a travelling detector AGATA will be employed at all major current and near-future European research facilities delivering stable and radioactive ion beams.
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Metastable States of 92,94Se: Identification of an Oblate K Isomer of 94Se and the Ground-State Shape Transition between N=58 and 60. Lizarazo, C.; Söderström, P.-A.; Werner, V.; Pietralla, N.; Walker, P. M.; Dong, G. X.; Xu, F. R.; Rodr\'{i}guez, T. R.; Browne, F.; Doornenbal, P.; Nishimura, S.; Niifmmode \mbox{\c{t}}else \c{t}\fi{}ifmmode \u{a}else \u{a}\fi{}, C. R.; Obertelli, A.; Ando, T.; Arici, T.; Authelet, G.; Baba, H.; Blazhev, A.; Bruce, A. M.; Calvet, D.; Caroll, R. J.; Château, F.; Chen, S.; Chung, L. X.; Corsi, A.; Cortés, M. L.; Delbart, A.; Dewald, M.; Ding, B.; Flavigny, F.; Franchoo, S.; Gerl, J.; Gheller, J.-M.; Giganon, A.; Gillibert, A.; Górska, M.; Gottardo, A.; Kojouharov, I.; Kurz, N.; Lapoux, V.; Lee, J.; Lettmann, M.; Linh, B. D.; Liu, J. J.; Liu, Z.; Momiyama, S.; Moschner, K.; Motobayashi, T.; Nagamine, S.; Nakatsuka, N.; Niikura, M.; Nobs, C.; Olivier, L.; Patel, Z.; Paul, N.; Podolyák, Zs.; Roussé, J.-Y.; Rudigier, M.; Saito, T. Y.; Sakurai, H.; Santamaria, C.; Schaffner, H.; Shand, C.; Stefan, I.; Steppenbeck, D.; Taniuchi, R.; Uesaka, T.; Vaquero, V.; Wimmer, K.; Xu, Z. in Phys. Rev. Lett. (2020). 124(22) 222501.
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Octupole states in 207Tl studied through β decay. Berry, T. A.; Podolyák, Zs.; Carroll, R. J.; Lică, R.; Brown, B. A.; Grawe, H.; Sotty, Ch.; Timofeyuk, N. K.; Alexander, T.; Andreyev, A. N.; Ansari, S.; Borge, M. J. G.; Brunet, M.; Cresswell, J. R.; Fahlander, C.; Fraile, L. M.; Fynbo, H. O. U.; Gamba, E.; Gelletly, W.; Gerst, R.-B.; Górska, M.; Gredley, A.; Greenlees, P.; Harkness-Brennan, L. J.; Huyse, M.; Judge, S. M.; Judson, D. S.; Konki, J.; Kowalska, M.; Kurcewicz, J.; Kuti, I.; Lalkovski, S.; Lazarus, I.; Lund, M.; Madurga, M.; Mărginean, N.; Mărginean, R.; Marroquin, I.; Mihai, C.; Mihai, R. E.; Nácher, E.; Negret, A.; Nae, S.; Niţă, C.; Pascu, S.; Page, R. D.; Patel, Z.; Perea, A.; Phrompao, J.; Piersa, M.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Regan, P. H.; Rotaru, F.; Rudigier, M.; Shand, C. M.; Shearman, R.; Simpson, E. C.; Stegemann, S.; Stora, T.; Tengblad, O.; Turturica, A.; Van Duppen, P.; Vedia, V.; Walker, P. M.; Warr, N.; Wearing, F. P.; H., De Witte in Phys. Rev. C, (A. P. Society, Hrsg.) (2020). 101 054311.
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Studying the Exotic Decay 70Kr to 70Br. Vitéz-Sveiczer, A.; Algora, A.; Morales, A.I.; Rubio, B.; Kiss, G.G.; de Angelis, G.; Recchia, F.; Nishimura, S.; Agramunt, J.; Guadilla, V.; Montaner-Pizá, A.; Orrigo, S.E.A.; Horváth, A.; Napoli, D.; Lenzi, S.; Boso, A.; Phong, V.H.; Wu, J.; Söderström, P.-A.; Sumikama, T.; Suzuki, H.; Takeda, H.; Ahn, D.S.; Baba, H.; Doornenbal, P.; Fukuda, N.; Inabe, N.; Isobe, T.; Kubo, T.; Kubono, S.; Sakurai, H.; Shimizu, Y.; Chen, S.; Blank, B.; Ascher, P.; Gerbaux, M.; Goigoux, T.; Giovinazzo, J.; Grévy, S.; Kurtukián Nieto, T.; Magron, C.; Gelletly, W.; Dombrádi, Zs.; Fujita, Y.; Tanaka, M.; Aguilera, P.; Molina, F.; Eberth, J.; Diel, F.; Lubos, D.; Borcea, C.; Ganioglu, E.; Nishimura, D.; Oikawa, H.; Takei, Y.; Yagi, S.; Korten, W.; de France, G.; Davies, P.; Liu, J.; Lee, J.; Lokotko, T.; Kojouharov, I.; Kurz, N.; Shaffner, H. in Acta Physica Polonica B (2020). 51(3) 587-594.
Beta-decay of the very neutron-deficient Kr isotope, 70Kr, was studied at RIKEN-RIBF using the EURICA cluster array. The experiment significantly increased our knowledge of the beta-decay of this isotope. Namely, 16 new γ-ray transitions were identified and the half-life was derived from time correlations of the beta particles (tiβ1/2=(44.99±0.16) ms) and from the decay curves of the observed γ-ray transitions (tiβγ1/2=(45.16±0.71) ms), respectively.
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Shape coexistence and multiparticle-multihole structures in 110,112Cd. Garrett, P. E.; Rodríguez, T. R.; Diaz Varela, A.; Green, K. L.; Bangay, J.; Finlay, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D. S.; Bildstein, V.; Colosimo, S.; Cross, D. S.; Demand, G. A.; Finlay, P.; Garnsworthy, A. B.; Grinyer, G. F.; Hackman, G.; Jigmeddorj, B.; Jolie, J.; Kulp, W. D.; Leach, K. G.; Morton, A. C.; Orce, J. N.; Pearson, C. J.; Phillips, A. A.; Radich, A. J.; Rand, E. T.; Schumaker, M. A.; Svensson, C. E.; Sumithrarachchi, C.; Triambak, S.; Warr, N.; Wong, J.; Wood, J. L.; Yates, S. W. in Phys. Rev. C (2020). 101 044302.
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Detailed spectroscopy of doubly magic 132 Sn. Benito, J.; Fraile, L. M.; Korgul, A.; Piersa, M.; Adamska, E.; Andreyev, A. N.; Álvarez-Rodríguez, R.; Barzakh, A. E.; Benzoni, 6 G.; Berry, T.; Borge, M. J. G.; Carmona, M.; Chrysalidis, K.; Costache, C.; Cubiss, J. G.; Goodacre, T. Day; Witte, H. De; Fedorov, D. V.; Fedosseev, V. N.; Fernández-Martínez, G.; Fijałkowska, A.; Fila, M.; Fynbo, H.; Galaviz, D.; Galve, P.; García-Díez, M.; Greenlees, P. T.; Grzywacz, R.; Harkness-Brennan, L. J.; Henrich, C.; Huyse, M.; Ibáñez, P.; Illana, A.; Janas, Z.; Jolie, J.; Judson, D. S.; Karayonchev, V.; Kicińska-Habior, M.; Konki, J.; Kurcewicz, J.; Lazarus, I.; Lică, R.; López-Montes, A.; Lund, M.; Mach, H.; Madurga, M.; Marroquín, I.; Marsh, B.; Martínez, M. C.; Mazzocchi, C.; Mărginean, N.; Mărginean, R.; Miernik, K.; Mihai, C.; Mihai, R. E.; Nácher, E.; Negret, A.; Olaizola, B.; Page, R. D.; Paulauskas, S. V.; Pascu, S.; Perea, A.; Pucknell, V.; Rahkila, P.; Raison, C.; Rapisarda, E.; Régis, J.-M.; Rezynkina, K.; Rotaru, F.; Rothe, S.; Sánchez-Parcerisa, D.; Sánchez-Tembleque, V.; Schomacker, K.; Simpson, G. S.; Sotty, Ch.; Stan, L.; Stănoiu, M.; Stryjczyk, M.; Tengblad, O.; Turturica, A.; Udías, J. M.; Duppen, P. Van; Vedia, V.; Villa-Abaunza, A.; Viñals, S.; Walters, W. B.; Wadsworth, R.; Warr, N. in Phys. Rev. C (2020). (102) 014328.
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Half-life measurements in \($^{164,166}\mathrm{Dy}$\) using \($\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$\) fast-timing spectroscopy with the \($\ensuremath{\nu}$\)-Ball spectrometer. Canavan, R. L.; Rudigier, M.; Regan, P. H.; Lebois, M.; Wilson, J. N.; Jovancevic, N.; Söderström, P.-A.; Collins, S. M.; Thisse, D.; Benito, J.; Bottoni, S.; Brunet, M.; Cieplicka-Orynczak, N.; Courtin, S.; Doherty, D. T.; Fraile, L. M.; Hadynska-Klek, K.; Häfner, G.; Heine, M.; Iskra, \L{}. W.; Karayonchev, V.; Kennington, A.; Koseoglou, P.; Lotay, G.; Lorusso, G.; Nakhostin, M.; Nita, C. R.; Oberstedt, S.; Podolyák, Zs.; Qi, L.; Régis, J.-M.; Sánchez-Tembleque, V.; Shearman, R.; Vedia, V.; Witt, W. in Phys. Rev. C (2020). 101(2) 024313.
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Multi-quasiparticle sub-nanosecond isomers in W-178. Rudigier, M.; Walker, P.M.; Canavan, R.L.; Podolyák, Zs.; Regan, P.H.; Söderström, P.-A.; Lebois, M.; Wilson, J.N.; Jovancevic, N.; Blazhev, A.; Benito, J.; Bottoni, S.; Brunet, M.; Cieplicka-Orynczak, N.; Courtin, S.; Doherty, D.T.; Fraile, L.M.; Hadynska-Klek, K.; Heine, M.; Iskra, Ł.W.; Jolie, J.; Karayonchev, V.; Kennington, A.; Koseoglou, P.; Lotay, G.; Lorusso, G.; Nakhostin, M.; Nita, C.R.; Oberstedt, S.; Qi, L.; Régis, J.-M.; Sánchez-Tembleque, V.; Shearman, R.; Witt, W.; Vedia, V.; Zell, K.O. in Physics Letters B (2020). 801 135140.
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Search for proton emission of the isomeric 10+ state in Ni-54. Stahl, K.; Wendt, A.; Reiter, P.; Rudolph, D.; Blazhev, A.; Bruyneel, B.; Eberth, J.; Fahlander, C.; Fransen, C.; Golubev, P.; Hess, H.; Hoischen, R.; Holler, A.; Kalkühler, M.; Kotthaus, T.; Lersch, D.; Pascovici, G.; Seidlitz, M.; Siebeck, B.; Taprogge, J.; Warr, N.; Wiens, A.; Zell, O. in The European Physical Journal A (2020). 56(1) 22.
Several experiments were conducted at the 10 MV Van-de-Graaff tandem accelerator at the Institute of Nuclear Physics, Cologne, to detect proton emission from the isomeric 6457-keV {\\($}{\$\)}10^+{\\($}{\$\)}10+ state in {\\($}{\$\)}^{\{}54{\}}{backslash}hbox {\{}Ni{\}}{\\($}{\$\)}54Ni. Excitation functions for two fusion--evaporation reactions were measured to maximise the population of the rare two-neutron evaporation channel from a {\\($}{\$\)}^{\{}56{\}}{backslash}hbox {\{}Ni{\}}{\\($}{\$\)}56Ni compound nucleus. The search for delayed proton emission was based on the {\\($}{\$\)}^{\{}28{\}}{backslash}hbox {\{}Si{\}}{\\($}{\$\)}28Si({\\($}{\$\)}^{\{}28{\}}{backslash}hbox {\{}Si{\}},2n{\\($}{\$\)}28Si,2n){\\($}{\$\)}^{\{}54{\}}{backslash}hbox {\{}Ni{\}}{\\($}{\$\)}54Ni reaction at a beam energy of 70 MeV. For this reaction, a cross-section limit for the population of the {\\($}{\$\)}10^+{\\($}{\$\)}10+ state in {\\($}{\$\)}^{\{}54{\}}{backslash}hbox {\{}Ni{\}}{\\($}{\$\)}54Ni and its proton-decay branch was determined to be {\\($}{\$\)}{backslash}sigma < 22{\\($}{\$\)}\($\sigma$\)<22 nb.
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γ-ray tracking with AGATA: A new perspective for spectroscopy at radioactive ion beam facilities. Reiter, P. in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (2020). 463 221 - 226.
The Advanced GAmma Tracking Array (AGATA) is a next generation high-resolution γ-ray spectrometer for nuclear structure studies based on the principle of γ-ray tracking. It is built from high-fold segmented germanium detectors which will operate in position-sensitive mode by employing digital electronics and pulse-shape decomposition algorithms. The unique combination of highest detection efficiency and position sensitivity allows spectroscopic studies with instable ion beams of lowest intensity. The first implementation of the array consisted of five AGATA modules; it was operated at INFN Legnaro. A larger array of AGATA modules was used at GSI for experiments with unstable ion beams at relativistic energies. At the moment the spectrometer is hosted by GANIL. In the near future AGATA will be employed at the leading infrastructures for nuclear structure studies in Europe. The presentation will illustrate the potential of the novel gamma-ray tracking method by physics cases from the different exploitation sites. Perspectives and opportunities for γ-ray spectroscopy at future radioactive ion beam facilities are presented and discussed.
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Evolution of Octupole Deformation in Radium Nuclei from Coulomb Excitation of Radioactive Ra-222 and Ra-228 Beams. Butler, P. A.; Gaffney, L. P.; Spagnoletti, P.; Abrahams, K.; Bowry, M.; Cederkäll, J.; de Angelis, G.; De Witte, H.; Garrett, P. E.; Goldkuhle, A.; Henrich, C.; Illana, A.; Johnston, K.; Joss, D. T.; Keatings, J. M.; Kelly, N. A.; Komorowska, M.; Konki, J.; Kröll, T.; Lozano, M.; Nara Singh, B. S.; O'Donnell, D.; Ojala, J.; Page, R. D.; Pedersen, L. G.; Raison, C.; Reiter, P.; Rodriguez, J. A.; Rosiak, D.; Rothe, S.; Scheck, M.; Seidlitz, M.; Shneidman, T. M.; Siebeck, B.; Sinclair, J.; Smith, J. F.; Stryjczyk, M.; Van Duppen, P.; Vinals, S.; Virtanen, V.; Warr, N.; Wrzosek-Lipska, K.; Zielińska, M. in Phys. Rev. Lett. (2020). 124(4) 042503.
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Low-Z boundary of the N=88-90 shape phase transition: Ce-148 near the critical point. Koseoglou, P.; Werner, V.; Pietralla, N.; Ilieva, S.; Nikšić, T.; Vretenar, D.; Alexa, P.; Thürauf, M.; Bernards, C.; Blanc, A.; Bruce, A. M.; Cakirli, R. B.; Cooper, N.; Fraile, L. M.; de France, G.; Jentschel, M.; Jolie, J.; Köster, U.; Korten, W.; Kröll, T.; Lalkovski, S.; Mach, H.; Mărginean, N.; Mutti, P.; Patel, Z.; Paziy, V.; Podolyák, Zs.; Regan, P. H.; Régis, J.-M.; Roberts, O. J.; Saed-Samii, N.; Simpson, G. S.; Soldner, T.; Ur, C. A.; Urban, W.; Wilmsen, D.; Wilson, E. in Phys. Rev. C (2020). 101(1) 014303.
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γ-γ fast timing at X-ray energies and investigation on various timing deviations. Régis, J.-M.; Esmaylzadeh, A.; Jolie, J.; Karayonchev, V.; Knafla, L.; Köster, U.; Kim, Y.H.; Strub, E. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2020). 955 163258.
We report on systematic γ-γ fast-timing measurements by using four cylindrical 1.5′′×1.5′′ LaBr3(Ce) scintillator detectors which were installed in compact geometry around the focal plane of the Lohengrin fission-fragment separator at the Institut Laue–Langevin in Grenoble, France. Unconventional γ-ray sources as 185Os and 187W were produced by thermal-neutron activation to provide nearly prompt low-energy γ and K-X rays with average γ- and X-ray multiplicity equal to two. Due to practically no contribution of Compton background, highly precise results of time-walk measurements down to 40 keV are presented. Timing deviations related to different phenomena have been investigated, such as the geometry of an extended γ-ray source and the detector arrangement, long-term timing shifts and the timing contributions of the Compton background and the inter-detector Compton-scattering. The geometrical timing deviations are shown to be minimized using a multi-element detector array with a centrally symmetric arrangement relative to the center of the focal plane. Time-correction formula are proposed as analytical corrections for long-term time shifts, the time contributions of the Compton background and the position-dependent change of the time walk for cases where the calibration source cannot be placed at the center of the focal plane.
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Performing the differential decay curve method on γ-ray transitions with unresolved Doppler-shifted components. Barber, L.; Cullen, D.M.; Giles, M.M.; Singh, B.S. Nara; Mallaburn, M.J.; Beckers, M.; Blazhev, A.; Braunroth, T.; Dewald, A.; Fransen, C.; Goldkuhle, A.; Jolie, J.; Mammes, F.; Müller-Gatermann, C.; Wölk, D.; Zell, K.O. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2020). 950 162965.
A new method of extracting the γ-ray intensities necessary to perform lifetime measurements using the differential decay curve method (DDCM) is presented in this work, the unresolved Doppler-shifted components method (UDCM). The UDCM allows for a DDCM analysis to be performed using a γ-ray transition for which the fully Doppler-shifted and degraded components are unresolvable in energy and so are detected as a single peak. This technique was used to measure the known lifetime of the yrast 21+ state in 50Mn with a depopulating transition that does not have resolvable fully Doppler-shifted and degraded components. The lifetime measured through applying the UDCM was consistent with the standard DDCM measurement of the 21+ state. Use of the UDCM allows for DDCM lifetime measurements to be made using transitions of smaller γ-ray energies, smaller recoil velocities and, in some cases, with a smaller uncertainty. In contrast to a standard DDCM analysis, a UDCM analysis is also independent of the widths of the fully Doppler-shifted and degraded components and as a result they do not need to be determined.
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Isomer studies in the vicinity of the doubly-magic nucleus 100Sn: Observation of a new low-lying isomeric state in 97Ag. Hornung, Christine; Amanbayev, Daler; Dedes, Irene; Kripko-Koncz, Gabriella; Miskun, Ivan; Shimizu, Noritaka; Andrés, Samuel Ayet San; Bergmann, Julian; Dickel, Timo; Dudek, Jerzy; Ebert, Jens; Geissel, Hans; Górska, Magdalena; Grawe, Hubert; Greiner, Florian; Haettner, Emma; Otsuka, Takaharu; Plaß, Wolfgang R.; Purushothaman, Sivaji; Rink, Ann-Kathrin; Scheidenberger, Christoph; Weick, Helmut; Bagchi, Soumya; Blazhev, Andrey; Charviakova, Olga; Curien, Dominique; Finlay, Andrew; Kaur, Satbir; Lippert, Wayne; Otto, Jan-Hendrik; Patyk, Zygmunt; Pietri, Stephane; Tanaka, Yoshiki K.; Tsunoda, Yusuke; Winfield, John S. in Physics Letters B (2020). 802 135200.
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Spectroscopy of 99Cd and 101In from beta decays of 99In and 101Sn. Park, J.; Krücken, R.; Blazhev, A.; Lubos, D.; Gernhäuser, R.; Lewitowicz, M.; Nishimura, S.; Ahn, D. S.; Baba, H.; Blank, B.; Boutachkov, P.; Browne, F.; ifmmode \check{C}else \v{C}\fi{}elikoviifmmode \acute{c}else {{\'c}}\fi{}, I.; de France, G.; Doornenbal, P.; Faestermann, T.; Fang, Y.; Fukuda, N.; Giovinazzo, J.; Goel, N.; Górska, M.; Grawe, H.; Ilieva, S.; Inabe, N.; Isobe, T.; Jungclaus, A.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Kwon, Y. K.; Lorusso, G.; Moschner, K.; Murai, D.; Nishizuka, I.; Patel, Z.; Rajabali, M. M.; Rice, S.; Sakurai, H.; Schaffner, H.; Shimizu, Y.; Sinclair, L.; Söderström, P.-A.; Steiger, K.; Sumikama, T.; Suzuki, H.; Takeda, H.; Wang, Z.; Watanabe, H.; Wu, J.; Xu, Z. Y. in Phys. Rev. C (2020). 102(1) 014304.
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Lifetime measurements of 162Er: Evolution of collectivity in the rare-earth region. Knafla, L.; Häfner, G.; Jolie, J.; Régis, J.-M.; Karayonchev, V.; Blazhev, A.; Esmaylzadeh, A.; Fransen, C.; Goldkuhle, A.; Herb, S.; Müller-Gatermann, C.; Warr, N.; Zell, K. O. in Phys. Rev. C (2020). 102(4) 044310.
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Escape-suppression shield detector for the MINIBALL γ-ray spectrometer. Rosiak, D.; Seidlitz, M.; Reiter, P.; Eberth, J.; Hess, H.; Hirsch, R.; Steinbach, T.; Warr, N.; Le Galliard, C.; Matea, I.; Nguyen Trung, T.; Gottardo, A. in The European Physical Journal A (2019). 55(4) 48.
A bismuth-germanate (BGO) escape-suppression shield for the high-purity germanium triple-cluster detector of the MINIBALL {\\($} {\backslash}gamma{\$\)}\($\gamma$\)-ray spectrometer was designed and built. Monte Carlo simulations with the simulation code GEANT4 were performed to guide the construction and to determine the detector geometry of the new BGO shield. After the first measurements concerning mechanical properties of the BGO housing and the performance of the photomultiplier tubes at the Institut de Physique Nucl{é}aire, Orsay, the prototype BGO escape-suppression shield was combined with a MINIBALL triple-cluster detector at the Institut f{ü}r Kernphysik, Cologne. A dedicated electronics and digital data-acquisition system was put into operation in order to determine timing properties of the combined coincidence measurement and to measure values for the energy resolution of the BGO detectors, for the BGO low-energy threshold, and for the crucial peak-to-total ratio (P/T). The measured P/T value for a standard 60Co {\\($} {\backslash}gamma{\$\)}\($\gamma$\)-ray source compares well with expectations and will allow to proceed with the amendment of the MINIBALL triple-cluster detectors with an escape-suppression shield for improved in-beam {\\($} {\backslash}gamma{\$\)}\($\gamma$\)-ray spectroscopy especially at the new HIE-ISOLDE accelerator for radioactive ion beams at CERN.
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Electromagnetic properties of low-lying states in neutron-deficient Hg isotopes: Coulomb excitation of ¹⁸²Hg, ¹⁸⁴Hg, ¹⁸⁶Hg and ¹⁸⁸Hg. Wrzosek-Lipska, K.; Rezynkina, K.; Bree, N.; Zielińska, M.; Gaffney, L. P.; Petts, A.; Andreyev, A.; Bastin, B.; Bender, M.; Blazhev, A.; Bruyneel, B.; Butler, P. A.; Carpenter, M. P.; Cederkäll, J.; Clément, E.; Cocolios, T. E.; Deacon, A. N.; Diriken, J.; Ekström, A.; Fitzpatrick, C.; Fraile, L. M.; Fransen, Ch.; Freeman, S. J.; García-Ramos, J. E.; Geibel, K.; Gernhäuser, R.; Grahn, T.; Guttormsen, M.; Hadinia, B.; Hadyńska-Klȩk, K.; Hass, M.; Heenen, P. H.; Herzberg, R. D.; Hess, H.; Heyde, K.; Huyse, M.; Ivanov, O.; Jenkins, D. G.; Julin, R.; Kesteloot, N.; Kröll, Th.; Krücken, R.; Larsen, A. C.; Lutter, R.; Marley, P.; Napiorkowski, P. J.; Orlandi, R.; Page, R. D.; Pakarinen, J.; Patronis, N.; Peura, P. J.; Piselli, E.; Próchniak, L.; Rahkila, P.; Rapisarda, E.; Reiter, P.; Robinson, A. P.; Scheck, M.; Siem, S.; Singh Chakkal, K.; Smith, J. F.; Srebrny, J.; Stefanescu, I.; Tveten, G. M.; Van Duppen, P.; Van de Walle, J.; Voulot, D.; Warr, N.; Wiens, A.; Wood, J. L. in The European Physical Journal A (2019). 55(8) 130.
The neutron-deficient mercury isotopes serve as a classical example of shape coexistence, whereby at low energy near-degenerate nuclear states characterized by different shapes appear. The electromagnetic structure of even-mass 182-188 Hg isotopes was studied using safe-energy Coulomb excitation of neutron-deficient mercury beams delivered by the REX-ISOLDE facility at CERN. The population of {\\($} 0^{\{}+{\}}{\_}{\{}1,2{\}}{\$\)}01,2+, {\\($} 2^{\{}+{\}}{\_}{\{}1,2{\}}{\$\)}21,2+and {\\($} 4^{\{}+{\}}{\_}{\{}1{\}}{\$\)}41+states was observed in all nuclei under study. Reduced E2 matrix elements coupling populated yrast and non-yrast states were extracted, including their relative signs. These are a sensitive probe of shape coexistence and may be used to validate nuclear models. The experimental results are discussed in terms of mixing of two different configurations and are compared with three different model calculations: the Beyond Mean Field model, the Interacting Boson Model with configuration mixing and the General Bohr Hamiltonian. Partial agreement with experiment was observed, hinting to missing ingredients in the theoretical descriptions.
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The concept of nuclear photon strength functions: A model-independent approach via ((gamma)over-right-arrow, gamma ` gamma `') reactions. Isaak, J.; Savran, D.; Loher, B.; Beck, T.; Bhike, M.; Gayer, U.; Krishichayan,; Pietralla, N.; Scheck, M.; Tornow, W.; Werner, V.; Zilges, A.; Zweidinger, M. in Physics Letters B (2019). 788 225-230.
Most theoretical approaches used in nuclear astrophysics to model the nucleosynthesis of heavy elements incorporate the so-called statistical model in order to describe the excitation and decay properties of atomic nuclei. One of the basic assumptions of this model is the validity of the Brink-Axel hypothesis and the related concept of so-called photon strength functions to describe gamma-ray transition probabilities. We present a novel experimental approach that allows for the first time to experimentally determine the photon strength function simultaneously in two independent ways by a unique combination of quasimonochromatic photon beams and a newly implemented gamma-gamma coincidence setup. This technique does not assume a priori the validity of the Brink-Axel hypothesis and sets a benchmark in terms of the detection sensitivity for measuring decay properties of photo-excited states below the neutron separation energy. The data for the spherical off-shell nucleus Te-128 were obtained for y-ray beam-energy settings between 3 MeV and 9 MeV in steps of 130 keV for the lower beam energies and in steps of up to 280 keV for the highest beam settings. We present a quantitative analysis on the consistency of the derived photon strength function with the Brink-Axel hypothesis. The data clearly demonstrate a discrepancy of up to a factor of two between the photon strength functions extracted from the photoabsorption and photon emission process, respectively. In addition, we observe that the photon strength functions are not independent of the excitation energy, as usually assumed. Thus, we conclude, that the Brink-Axel hypothesis is not strictly fulfilled in the excitation-energy region below the neutron separation threshold S-n= 8.78 MeV) for the studied case of Te-128. (C) 2018 The Authors. Published by Elsevier B.V.
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Multiple Shape Coexistence in 110,112Cd. Garrett, P. E.; Rodríguez, T. R.; Varela, A. Diaz; Green, K. L.; Bangay, J.; Finlay, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D. S.; Bildstein, V.; Colosimo, S.; Cross, D. S.; Demand, G. A.; Finlay, P.; Garnsworthy, A. B.; Grinyer, G. F.; Hackman, G.; Jigmeddorj, B.; Jolie, J.; Kulp, W. D.; Leach, K. G.; Morton, A. C.; Orce, J. N.; Pearson, C. J.; Phillips, A. A.; Radich, A. J.; Rand, E. T.; Schumaker, M. A.; Svensson, C. E.; Sumithrarachchi, C.; Triambak, S.; Warr, N.; Wong, J.; Wood, J. L.; Yates, S. W. in Phys. Rev. Lett. (2019). 123(14) 142502.
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Low-lying dipole strength in the well-deformed nucleus Gd-156. Tamkas, M.; Aciksoez, E.; Isaak, J.; Beck, T.; Benouaret, N.; Bhike, M.; Boztosun, I.; Durusoy, A.; Gayer, U.; Krishichayan,; Loeher, B.; Pietralla, N.; Savran, D.; Tornow, W.; Werner, V.; Zilges, A.; Zweidinger, M. in Nuclear Physics A (2019). 987 79-89.
The low-lying dipole strength of the deformed nucleus Gd-156 was investigated in the energy region from 3.1 MeV to 6.2 MeV using the method of nuclear resonance fluorescence (NRF). The NRF experiments were performed at the Darmstadt High Intensity Photon Setup (DHIPS) at Technische Universitat Darmstadt using unpolarized continuous-energy bremsstrahlung and at the High-Intensity gamma-ray Source (HI gamma S) at Duke University using quasi-monoenergetic and linearly-polarized photon beams. The combination of both experiments allows to separate electric and magnetic contributions and to determine absolute transition strengths for individual excited states as well as averaged quantities over narrow excitation energy regions. The investigated energy regions cover the region of the scissors mode as well as the low-energy part of the Pygmy Dipole Resonance. This is the first experiment where both of these excitation modes as well as the region in between has been successfully studied in a deformed heavy nucleus using the NRF method. (C) 2019 Elsevier B.V. All rights reserved.
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Beta decay of 133In: gamma emission from neutron-unbound states in 133Sn. Piersa, M.; Korgul, A.; Fraile, L. M.; Benito, J.; Adamska, E.; Andreyev, A. N.; Álvarez-Rodr\'{i}guez, R.; Barzakh, A. E.; Benzoni, G.; Berry, T.; Borge, M. J. G.; Carmona, M.; Chrysalidis, K.; Correia, J. G.; Costache, C.; Cubiss, J. G.; Day Goodacre, T.; De Witte, H.; Fedorov, D. V.; Fedosseev, V. N.; Fernández-Mart\'{i}nez, G.; Fija\l{}kowska, A.; Fila, M.; Fynbo, H.; Galaviz, D.; Greenlees, P. T.; Grzywacz, R.; Harkness-Brennan, L. J.; Henrich, C.; Huyse, M.; Illana, A.; Janas, Z.; Johnston, K.; Judson, D. S.; Karanyonchev, V.; Kiciifmmode \acute{n}else {{\'n}}\fi{}ska Habior, M.; Konki, J.; Kurcewicz, J.; Lazarus, I.; Licifmmode \u{a}else \u{a}\fi{}, R.; Mach, H.; Madurga, M.; Marroqu\'{i}n, I.; Marsh, B.; Mart\'{i}nez, M. C.; Mazzocchi, C.; Mifmmode \u{a}else \u{a}\fi{}rginean, N.; Mifmmode \u{a}else \u{a}\fi{}rginean, R.; Miernik, K.; Mihai, C.; Nácher, E.; Negret, A.; Olaizola, B.; Page, R. D.; Paulaskalas, S.; Pascu, S.; Perea, A.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Régis, J.-M.; Rotaru, F.; Rothe, S.; Sánchez-Tembleque, V.; Simpson, G.; Sotty, Ch.; Stan, L.; Stifmmode \u{a}else \u{a}\fi{}noiu, M.; Stryjczyk, M.; Tengblad, O.; Turturica, A.; Ud\'{i}as, J. M.; Van Duppen, P.; Vedia, V.; Villa, A.; Vi nals, S.; Wadsworth, R.; Walters, W. B.; Warr, N. in Phys. Rev. C (2019). 99(2) 024304.
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Lifetimes and shape-coexisting states of 99Zr. Spagnoletti, P.; Simpson, G.; Kisyov, S.; Bucurescu, D.; Régis, J.-M.; Saed-Samii, N.; Blanc, A.; Jentschel, M.; Köster, U.; Mutti, P.; Soldner, T.; de France, G.; Ur, C. A.; Urban, W.; Bruce, A. M.; Bernards, C.; Drouet, F.; Fraile, L. M.; Gaffney, L. P.; Ghitifmmode \u{a}else \u{a}\fi{}, D. G.; Ilieva, S.; Jolie, J.; Korten, W.; Kröll, T.; Lalkovski, S.; Larijarni, C.; Licifmmode \u{a}else \u{a}\fi{}, R.; Mach, H.; Mifmmode \u{a}else \u{a}\fi{}rginean, N.; Paziy, V.; Podolyák, Zs.; Regan, P. H.; Scheck, M.; Smith, J. F.; Thiamova, G.; Townsley, C.; Vancraeyenest, A.; Vedia, V.; Warr, N.; Werner, V.; Zieliifmmode \acute{n}else {{\'n}}\fi{}ska, M. in Phys. Rev. C (2019). 100(1) 014311.
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Pulse-Shape Analysis and position resolution in highly segmented HPGe AGATA detectors. Lewandowski, L.; Reiter, P.; Birkenbach, B.; Bruyneel, B.; Clement, E.; Eberth, J.; Hess, H.; Michelagnoli, C.; Li, H.; Perez-Vidal, R. M.; Zielinska, M. in The European Physical Journal A (2019). 55(5) 81.
The performance of the Pulse-Shape Analysis (PSA) in AGATA HPGe detectors was investigated and improved employing a {\\($}{\backslash}gamma{\$\)}\($\gamma$\)-ray source measurement based on {\\($} e^{\{}+{\}}e^{\{}-{\}}{\$\)}e+e-annihilation radiation after decays of 22Na by {\\($} {\backslash}beta^{\{}+{\}}{\$\)}\($\beta$\)+decay. The first interaction positions of the two 511keV {\\($}{\backslash}gamma{\$\)}\($\gamma$\)rays were determined and the connecting line of these two positions was compared to the known source position as a measure for the PSA performance. The position resolution and its dependence on the PSA parameters were investigated by varying most relevant input quantities: the charge carrier mobility of the holes, the response of the employed measuring electronics especially the preamplifier rise time. The relative statistical weight of charge signals and transient signals was scrutinized. The optimal distance metric of the grid-search algorithm and its impact on the position resolution were determined.
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Investigation of the Δn = 0 selection rule in Gamow-Teller transitions: The β-decay of 207Hg. Berry, T.A.; Podolyák, Zs.; Carroll, R.J.; Lică, R.; Grawe, H.; Timofeyuk, N.K.; Alexander, T.; Andreyev, A.N.; Ansari, S.; Borge, M.J.G.; Creswell, J.; Fahlander, C.; Fraile, L.M.; Fynbo, H.O.U.; Gelletly, W.; Gerst, R.-B.; Górska, M.; Gredley, A.; Greenlees, P.; Harkness-Brennan, L.J.; Huyse, M.; Judge, S.M.; Judson, D.S.; Konki, J.; Kurcewicz, J.; Kuti, I.; Lalkovski, S.; Lazarus, I.; Lund, M.; Madurga, M.; Mărginean, N.; Mărginean, R.; Marroquin, I.; Mihai, C.; Mihai, R.E.; Nácher, E.; Nae, S.; Negret, A.; Niţă, C.; Page, R.D.; Pascu, S.; Patel, Z.; Perea, A.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Regan, P.H.; Rotaru, F.; Shand, C.M.; Simpson, E.C.; Sotty, Ch.; Stegemann, S.; Stora, T.; Tengblad, O.; Turturica, A.; Duppen, P. Van; Vedia, V.; Wadsworth, R.; Walker, P.M.; Warr, N.; Wearing, F.; Witte, H. De in Physics Letters B (2019). 793 271 - 275.
Gamow-Teller β decay is forbidden if the number of nodes in the radial wave functions of the initial and final states is different. This Δn=0 requirement plays a major role in the β decay of heavy neutron-rich nuclei, affecting the nucleosynthesis through the increased half-lives of nuclei on the astrophysical r-process pathway below both Z=50 (for N>82) and Z=82 (for N>126). The level of forbiddenness of the Δn=1ν1g9/2→π0g7/2 transition has been investigated from the β− decay of the ground state of 207Hg into the single-proton-hole nucleus 207Tl in an experiment at the ISOLDE Decay Station. From statistical observational limits on possible γ-ray transitions depopulating the π0g7/2−1 state in 207Tl, an upper limit of 3.9×10−3% was obtained for the probability of this decay, corresponding to logft>8.8 within a 95% confidence limit. This is the most stringent test of the Δn=0 selection rule to date.
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Isomer spectroscopy in ¹³³Ba and high-spin structure of ¹³⁴Ba. Kaya, L.; Vogt, A.; Reiter, P.; Siciliano, M.; Shimizu, N.; Utsuno, Y.; Wang, H.-K.; Gargano, A.; Coraggio, L.; Itaco, N.; Arnswald, K.; Bazzacco, D.; Birkenbach, B.; Blazhev, A.; Bracco, A.; Bruyneel, B.; Corradi, L.; Crespi, F. C. L.; de Angelis, G.; Droste, M.; Eberth, J.; Esmaylzadeh, A.; Farnea, E.; Fioretto, E.; Fransen, C.; Gadea, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hadyńska-Klęk, K.; Hess, H.; Hirsch, R.; John, P. R.; Jolie, J.; Jungclaus, A.; Karayonchev, V.; Kornwebel, L.; Korten, W.; Leoni, S.; Lewandowski, L.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Müller-Gatermann, C.; Napoli, D.; Podolyák, Zs.; Pollarolo, G.; Recchia, F.; Régis, J.-M.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Schomacker, K.; Seidlitz, M.; Siebeck, B.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Szpak, B.; Teruya, E.; Ur, C.; Valiente-Dobón, J. J.; Wolf, K.; Yanase, K.; Yoshinaga, N.; Zell, K. O. in Phys. Rev. C (2019). 100(2) 024323.
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HIGH-RESOLUTION GAMMA-RAY SPECTROSCOPY WITH ELIADE AT THE EXTREME LIGHT INFRASTRUCTURE. Soderstrom, P-A; Suliman, G.; Ur, C. A.; Balabanski, D.; Beck, T.; Capponi, L.; Dhal, A.; Iancu, V; Ilie, S.; Iovea, M.; Kusoglu, A.; Petcu, C.; Pietralla, N.; {Turturica, V}; Udup, E.; Wilhelmy, J.; Zilges, A. in Acta Physica Polonica B (2019). 50(3) 329-338.
The Extreme Light Infrastructure is a major European undertaking with the aim of constructing a set of facilities that can produce the worlds highest intensity laser beams as well as unique high-brilliance, narrow-bandwidth gamma-ray beams using laser-based inverse Compton scattering. The latter will be one of the unique features of the facility in Bucharest-Magurele, Romania, where the scientific focus will be towards Nuclear Physics And nuclear photonics both with high intensity lasers and gamma beams individually, as well as combined. One of the main instruments being constructed for the Nuclear Physics And applications with high-brilliance gamma-beams research activity is the ELIADE gamma-ray detector array. This array consists of eight segmented HPGe clover detectors as well as large-volume LaBr3 detectors. The nuclear physics topics are expected to cover a large range including, but not limited to, properties of pygmy resonance and collective scissors mode excitations, parity violation in nuclear excitations, and matrix elements for neutrinoless double-beta decay. However, the uniqueness of the environment in which ELIADE will operate presents several challenges in the design and construction of the array. Here, we discuss some of these challenges and how we plan to overcome them, as well as the current status of implementation.
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Spectroscopy and excited-state g factors in weakly collective ¹¹¹Cd: Confronting collective and microscopic models. Coombes, B. J.; Stuchbery, A. E.; Blazhev, A.; Grawe, H.; Reed, M. W.; Akber, A.; Dowie, J. T. H.; Gerathy, M. S. M.; Gray, T. J.; Kibédi, T.; Mitchell, A. J.; Palazzo, T. in Phys. Rev. C (2019). 100(2) 024322.
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New lifetime measurements for the lowest quadrupole states in 20,22Ne and possible explanations of the high collectivity of the depopulating E2 transitions. Petkov, P.; Müller-Gatermann, C.; Werner, D.; Dewald, A.; Blazhev, A.; Fransen, C.; Jolie, J.; Ohkubo, S.; Zell, K. O. in Phys. Rev. C (2019). 100(2) 024312.
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Properties of \($\ensuremath{\gamma}$\)-decaying isomers in the \($^{100}\mathrm{Sn}$\) region populated in fragmentation of a \($^{124}\mathrm{Xe}$\) beam. Häfner, G.; Moschner, K.; Blazhev, A.; Boutachkov, P.; Davies, P. J.; Wadsworth, R.; Ameil, F.; Baba, H.; Bäck, T.; Dewald, M.; Doornenbal, P.; Faestermann, T.; Gengelbach, A.; Gerl, J.; Gernhäuser, R.; Go, S.; Górska, M.; Grawe, H.; Gregor, E.; Hotaka, H.; Isobe, T.; Jenkins, D. G.; Jolie, J.; Jung, H. S.; Kojouharov, I.; Kurz, N.; Lewitowicz, M.; Lorusso, G.; Lozeva, R.; Merchan, E.; Naqvi, F.; Nishibata, H.; Nishimura, D.; Nishimura, S.; Pietralla, N.; Schaffner, H.; Söderström, P.-A.; Steiger, K.; Sumikama, T.; Taprogge, J.; Thöle, P.; Watanbe, H.; Warr, N.; Werner, V.; Xu, Z. Y.; Yagi, A.; Yoshinaga, K.; Zhu, Y. in Phys. Rev. C (2019). 100(2) 024302.
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The observation of vibrating pear-shapes in radon nuclei. Butler, P. A.; Gaffney, L. P.; Spagnoletti, P.; Konki, J.; Scheck, M.; Smith, J. F.; Abrahams, K.; Bowry, M.; Cederkäll, J.; Chupp, T.; de Angelis, G.; De Witte, H.; Garrett, P. E.; Goldkuhle, A.; Henrich, C.; Illana, A.; Johnston, K.; Joss, D. T.; Keatings, J. M.; Kelly, N. A.; Komorowska, M.; Kröll, T.; Lozano, M.; Nara Singh, B. S.; O’Donnell, D.; Ojala, J.; Page, R. D.; Pedersen, L. G.; Raison, C.; Reiter, P.; Rodriguez, J. A.; Rosiak, D.; Rothe, S.; Shneidman, T. M.; Siebeck, B.; Seidlitz, M.; Sinclair, J.; Stryjczyk, M.; Van Duppen, P.; Vinals, S.; Virtanen, V.; Warr, N.; Wrzosek-Lipska, K.; Zielinska, M. in Nature Communications (2019). 10(1) 2473.
There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in 224Rn and 226Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment.
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Microscopic structure of coexisting 0⁺ states in ⁶⁸Ni probed via two-neutron transfer. Flavigny, F.; Elseviers, J.; Andreyev, A. N.; Bauer, C.; Bildstein, V.; Blazhev, A.; Brown, B. A.; De Witte, H.; Diriken, J.; Fedosseev, V. N.; Franchoo, S.; Gernhäuser, R.; Huyse, M.; Ilieva, S.; Klupp, S.; Kröll, Th.; Lutter, R.; Marsh, B. A.; Mücher, D.; Nowak, K.; Otsuka, T.; Pakarinen, J.; Patronis, N.; Raabe, R.; Recchia, F.; Reiter, P.; Roger, T.; Sambi, S.; Seidlitz, M.; Seliverstov, M. D.; Siebeck, B.; Tsunoda, Y.; Van Duppen, P.; Vermeulen, M.; Von Schmid, M.; Voulot, D.; Warr, N.; Wenander, F.; Wimmer, K. in Phys. Rev. C (2019). 99(5) 054332.
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Fine structure of the pygmy quadrupole resonance in Sn-112,Sn-114. Tsoneva, N.; Spieker, M.; Lenske, H.; Zilges, A. in Nuclear Physics A (2019). 990 183-198.
The electric quadrupole response in Sn-112,Sn-114 isotopes is investigated by energy-density functional (EDF) and three-phonon quasiparticle-phonon model (QPM) theory with special emphasis on electric quadrupole excitations located above the first collective 2(+) state and below 5 MeV. Additional quadrupole strength clustering as a sequence of states similar to the recently observed pygmy quadrupole resonance in Sn-124 is found. The spectral distributions and transition densities of these 2(+) states show special features being compatible with oscillations of a neutron skin against the isospin-symmetric nuclear core. Furthermore, two (p, p' gamma) Doppler-shift attenuation (DSA) coincidence experiments were performed at the SONIC@HORUS setup. 2(+) states with excitation energies up to 4.2 MeV were populated in Sn-112,Sn-114. Lifetimes and branching ratios were measured allowing for the determination of E2 transition strengths to the ground state. A stringent comparison of the new data to EDF+QPM theory in Sn-112 and Sn-114 isotopes hints at the occurrence of a low-energy quadrupole mode of unique character which could be interpreted as pygmy quadrupole resonance. (C) 2019 Elsevier B.V. All rights reserved.
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Cross section measurements of proton capture reactions on Mo isotopes relevant to the astrophysical p process. Foteinou, V.; Axiotis, M.; Harissopulos, S.; Dimitriou, P.; Provatas, G.; Lagoyannis, A.; Becker, H. W.; Rogalla, D.; Zilges, A.; Schreckling, A.; Endres, A. in The European Physical Journal A (2019). 55(5)
.Cross section measurements of (p,) reactions on the Mo isotopes have been performed at beam energies from 2 to 6.2 MeV that are relevant to the p-process. Partial cross sections and isomeric ratios were also determined for the Mo-92 case. Astrophysical S factors as well as reaction rates were derived from the experimental cross sections. Statistical model calculations were performed using the latest version (1.9) of the statistical model code TALYS and were compared with the new data. An overall good agreement between theory and experiment was found. In addition, the effect of different combinations of the nuclear input parameters entering the stellar reaction-rate calculations was investigated. It was found that, for certain combinations of optical-model potentials, nuclear level densities and -ray strength functions, the nuclear uncertainties propagated through the Hauser-Feshbach calculations are less than a factor of 2 which is well below the average discrepancies of the calculated p-nuclei abundances and the observations.
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Lifetimes of the \(${4}_{1}^{+}$\) states of 206Po and 204Po: A study of the transition from noncollective seniority-like mode to collectivity. Stoyanova, M.; Rainovski, G.; Jolie, J.; Pietralla, N.; Blazhev, A.; Beckers, M.; Dewald, A.; Djongolov, M.; Esmaylzadeh, A.; Fransen, C.; Gerhard, L. M.; Gladnishki, K. A.; Herb, S.; John, P. R.; Karayonchev, V.; Keatings, J. M.; Kern, R.; Knafla, L.; Kocheva, D.; Kornwebel, L.; Kröll, Th.; Ley, M.; Mashtakov, K. M.; Müller-Gatermann, C.; Régis, J.-M.; Scheck, M.; Schomacker, K.; Sinclair, J.; Spagnoletti, P.; Sürder, C.; Warr, N.; Werner, V.; Wiederhold, J. in Phys. Rev. C (2019). 100(6) 064304.
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Lifetime measurements in 52,54Ti to study shell evolution toward N=32. Goldkuhle, A.; Fransen, C.; Blazhev, A.; Beckers, M.; Birkenbach, B.; Braunroth, T.; Clément, E.; Dewald, A.; Dudouet, J.; Eberth, J.; Hess, H.; Jacquot, B.; Jolie, J.; Kim, Y.-H.; Lemasson, A.; Lenzi, S. M.; Li, H. J.; Litzinger, J.; Michelagnoli, C.; Müller-Gatermann, C.; Nara Singh, B. S.; Pérez-Vidal, R. M.; Ralet, D.; Reiter, P.; Vogt, A.; Warr, N.; Zell, K. O.; Ataç, A.; Barrientos, D.; Barthe-Dejean, C.; Benzoni, G.; Boston, A. J.; Boston, H. C.; Bourgault, P.; Burrows, I.; Cacitti, J.; Cederwall, B.; Ciemala, M.; Cullen, D. M.; De France, G.; Domingo-Pardo, C.; Foucher, J.-L.; Fremont, G.; Gadea, A.; Gangnant, P.; González, V.; Goupil, J.; Henrich, C.; Houarner, C.; Jean, M.; Judson, D. S.; Korichi, A.; Korten, W.; Labiche, M.; Lefevre, A.; Legeard, L.; Legruel, F.; Leoni, S.; Ljungvall, J.; Maj, A.; Maugeais, C.; Ménager, L.; Ménard, N.; Menegazzo, R.; Mengoni, D.; Million, B.; Munoz, H.; Napoli, D. R.; Navin, A.; Nyberg, J.; Ozille, M.; Podolyak, Zs.; Pullia, A.; Raine, B.; Recchia, F.; Ropert, J.; Saillant, F.; Salsac, M. D.; Sanchis, E.; Schmitt, C.; Simpson, J.; Spitaels, C.; Stezowski, O.; Theisen, Ch.; Toulemonde, M.; Tripon, M.; Valiente Dobón, J.-J.; Voltolini, G.; Zielińska, M. in Phys. Rev. C (2019). 100(5) 054317.
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Atome, Kerne, Quarks - Alles begann mit Rutherford: Wie Teilchen-Streuexperimente uns die subatomare Welt erklären Paetz gen. Schieck, Hans in essentials (2019). Springer Spektrum.
Hans Paetz gen. Schieck zeigt in diesem essential nicht nur, wie rasant sich das Gebiet der Atome, Kerne und Teilchen bis zu den Quarks und Gluonen entwickelt hat. Er erläutert auch, wie alles begonnen hat – hier spielt die Person von Ernest Rutherford eine alles überragende Rolle. Das Gebiet der Kernphysik und unser Wissen über die Kerne haben sich seit 100 Jahren fundamental gewandelt. Aus eher philosophischen Vorstellungen haben sich konkrete Kenntnisse entwickelt über die Bausteine unserer Welt, deren Größe und hierarchische Ordnung und darüber, welche fundamentalen Kräfte zwischen ihnen wirken.
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Decay properties of the 3⁻₁ level in ⁹⁶Mo. Gregor, E T; Arsenyev, N N; Scheck, M; Shneidman, T M; Thürauf, M; Bernards, C; Blanc, A; Chapman, R; Drouet, F; Dzhioev, A A; de France, G; Jentschel, M; Jolie, J; Keatings, J M; Kröll, Th; Köster, U; Leguillon, R; Mashtakov, K R; Mutti, P; O'Donnell, D; Petrache, C M; Simpson, G S; Sinclair, J; Smith, J F; Soldner, T; Spagnoletti, P; Sushkov, A V; Urban, W; Vancraeyenest, A; Vanhoy, J R; Werner, V; Zell, K O; Zielinska, M in Journal of Physics G: Nuclear and Particle Physics (2019). 46(7) 075101.
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Evolution of E2 strength in the rare-earth isotopes ¹⁷⁴⁻¹⁷⁶⁻¹⁷⁸⁻¹⁸⁰Hf. Wiederhold, J.; Werner, V.; Kern, R.; Pietralla, N.; Bucurescu, D.; Carroll, R.; Cooper, N.; Daniel, T.; Filipescu, D.; Florea, N.; Gerst, R-B.; Ghita, D.; Gurgi, L.; Jolie, J.; Ilieva, R. S.; Lica, R.; Marginean, N.; Marginean, R.; Mihai, C.; Mitu, I. O.; Naqvi, F.; Nita, C.; Rudigier, M.; Stegemann, S.; Pascu, S.; Regan, P. H. in Phys. Rev. C (2019). 99(2) 024316.
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Lifetime measurement of excited states in ⁴⁶Ti. Goldkuhle, A.; Fransen, C.; Dewald, A.; Arnswald, K.; Bast, M.; Beckers, M.; Blazhev, A.; Braunroth, T.; Hackenberg, G.; Häfner, G.; Litzinger, J.; Jolie, J.; Müller-Gatermann, C.; von Spee, F.; Warr, N.; Werner, D.; Zell, K. O. in The European Physical Journal A (2019). 55(4) 53.
The level lifetimes of the yrast 21+, 41+ and 61+ states and an upper limit of the lifetime of the 81+ state in 46Ti have been measured with high accuracy exploiting the recoil distance Doppler-shift method (RDDS) and using {\\($}{\backslash}gamma{\backslash}gamma{\$\)}\($\gamma$\)\($\gamma$\)coincidences. The nuclei were populated by the fusion evaporation reaction 40Ca(9Be, 2p1n)46Ti at a beam energy of {\\($}E=33{\$\)}E=33MeV at the FN tandem accelerator of the University of Cologne, Germany. Lifetimes were extracted using the established differential decay curve method (DDCM).
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Probing isospin symmetry in the (⁵⁰Fe, ⁵⁰Mn, ⁵⁰Cr) isobaric triplet via electromagnetic transition rates. Giles, M. M.; Nara Singh, B. S.; Barber, L.; Cullen, D. M.; Mallaburn, M. J.; Beckers, M.; Blazhev, A.; Braunroth, T.; Dewald, A.; Fransen, C.; Goldkuhle, A.; Jolie, J.; Mammes, F.; Müller-Gatermann, C.; Wölk, D.; Zell, K. O.; Lenzi, S. M.; Poves, A. in Phys. Rev. C (2019). 99(4) 044317.
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Shape coexistence in 178Hg. Müller-Gatermann, C.; Dewald, A.; Fransen, C.; Auranen, K.; Badran, H.; Beckers, M.; Blazhev, A.; Braunroth, T.; Cullen, D. M.; Fruet, G.; Goldkuhle, A.; Grahn, T.; Greenlees, P. T.; Herzáifmmode \check{n}else \v{n}\fi{}, A.; Jakobsson, U.; Jenkins, D.; Jolie, J.; Julin, R.; Juutinen, S.; Konki, J.; Leino, M.; Litzinger, J.; Nomura, K.; Pakarinen, J.; Peura, P.; Procter, M. G.; Rahkila, P.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Scholey, C.; Sorri, J.; Stolze, S.; Taylor, M. J.; Uusitalo, J.; Zell, K. O. in Phys. Rev. C (2019). 99(5) 054325.
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Improvements in the measurement of small 14CO2 samples at {CologneAMS}. Stolz, A.; Dewald, A.; Heinze, S.; Altenkirch, R.; Hackenberg, G.; Herb, S.; Müller-Gatermann, C.; Schiffer, M.; Zitzer, G.; Wotte, A.; Rethemeyer, J.; Dunai, T. in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (2019). 439 70--75.
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Operating the 120{textdegree} Dipol-Magnet at the {CologneAMS} in a gas-filled mode. Altenkirch, R.; Feuerstein, C.; Schiffer, M.; Hackenberg, G.; Heinze, S.; Müller-Gatermann, C.; Dewald, A. in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (2019). 438 184--188.
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Toward the limit of nuclear binding on the N=Z line: Spectroscopy of ⁹⁶Cd. Davies, P. J.; Park, J.; Grawe, H.; Wadsworth, R.; Gernhäuser, R.; Krücken, R.; Nowacki, F.; Ahn, D. S.; Ameil, F.; Baba, H.; Bäck, T.; Blank, B.; Blazhev, A.; Boutachkov, P.; Browne, F.; Čeliković, I.; Dewald, M.; Doornenbal, P.; Faestermann, T.; Fang, Y.; de France, G.; Fukuda, N.; Gengelbach, A.; Gerl, J.; Giovinazzo, J.; Go, S.; Goel, N.; Górska, M.; Gregor, E.; Hotaka, H.; Ilieva, S.; Inabe, N.; Isobe, T.; Jenkins, D. G.; Jolie, J.; Jung, H. S.; Jungclaus, A.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Lewitowicz, M.; Lorusso, G.; Lubos, D.; Maier, L.; Merchan, E.; Moschner, K.; Murai, D.; Naqvi, F.; Nishibata, H.; Nishimura, D.; Nishimura, S.; Nishizuka, I.; Patel, Z.; Pietralla, N.; Rajabali, M. M.; Rice, S.; Sakurai, H.; Schaffner, H.; Shimizu, Y.; Sinclair, L. F.; Söderström, P.-A.; Steiger, K.; Sumikama, T.; Suzuki, H.; Takeda, H.; Taprogge, J.; Thöle, P.; Valder, S.; Wang, Z.; Warr, N.; Watanabe, H.; Werner, V.; Wu, J.; Xu, Z. Y.; Yagi, A.; Yoshinaga, K.; Zhu, Y. in Phys. Rev. C (2019). 99(2) 021302.
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Optimization and characterization of the PGAI-NT instrument's Neutron Tomography set-up at MLZ. Kluge, E. J.; Stieghorst, C.; Revay, Zs.; Kudejova, P.; Jolie, J. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2019). 932 1--15.
The Prompt Gamma-ray Activation Imaging and Neutron Tomography (PGAI-NT) instrument at the PGAA facility of the Heinz Maier-Leibnitz Center (MLZ), provides a method to obtain and effectively visualize position-sensitive element abundances in samples by combining a three-dimensional extension of Prompt Gamma-ray Activation Analysis (PGAA) and Neutron Tomography (NT). Inspired by a proof-of-principle study, a cone-beam tomography set-up was designed, tested and installed. This article reports on the design of the new cone-beam tomography set-up and its optimization using neutron beam simulations and physical measurements. A new position-sensitive neutron detector with improved performance and instrument environment integration was designed, built and tested. The overall NT performance of the set-up is investigated in the course of a Quality Assessment for neutron tomography sites. Its stand-alone NT and all-in-one PGAI-NT suitability is determined.
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Lifetimes in ²¹¹At and their implications for the nuclear structure above ²⁰⁸Pb. Karayonchev, V.; Blazhev, A.; Esmaylzadeh, A.; Jolie, J.; Dannhoff, M.; Diel, F.; Dunkel, F.; Fransen, C.; Gerhard, L. M.; Gerst, R.-B.; Knafla, L.; Kornwebel, L.; Müller-Gatermann, C.; Régis, J.-M.; Warr, N.; Zell, K. O.; Stoyanova, M.; Van Isacker, P. in Phys. Rev. C (2019). 99(2) 024326.
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STUDY OF DIPOLE EXCITATIONS IN Sn-124 VIA (p, p `gamma) AT 15 MeV. Faerber, M.; Bohn, A.; Everwyn, V; Muescher, M.; Pickstone, S. G.; Prill, S.; Scholz, P.; Spieker, M.; Weinert, M.; Wilhelmy, J.; Zilges, A. in Acta Physica Polonica B (2019). 50(3) 475-480.
An inelastic proton scattering experiment was performed with the combined setup SONIC@HORUS at a beam energy of 15 MeV in Cologne. First results for the deduced branching ratios as well as the E1 strength distribution obtained with the Sn-124(p, p'gamma) reaction are presented. Additionally, a qualitative comparison to excitations in experiments with different probes like (alpha, alpha'gamma) and (gamma, gamma') will be discussed.
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Normal and intruder configurations in 34Si populated in the beta-decay of 34Mg and 34Al. Lica, R.; Rotaru, F.; Borge, M. J. G.; Grévy, S.; Negoita, F.; Poves, A.; Sorlin, O.; Andreyev, A. N.; Borcea, R.; Costache, C.; De Witte, H.; Fraile, L. M.; Greenlees, P. T.; Huyse, M.; Ionescu, A.; Kisyov, S.; Konki, J.; Lazarus, I.; Madurga, M.; Mifmmode \u{a}else \u{a}\fi{}rginean, N.; Mifmmode \u{a}else \u{a}\fi{}rginean, R.; Mihai, C.; Mihai, R. E.; Negret, A.; Nowacki, F.; Page, R. D.; Pakarinen, J.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; ifmmode \mbox{\c{S}}else \c{S}\fi{}erban, A.; Sotty, C. O.; Stan, L.; Stifmmode \u{a}else \u{a}\fi{}noiu, M.; Tengblad, O.; Turturicifmmode \u{a}else \u{a}\fi{}, A.; Van Duppen, P.; Warr, N.; Dessagne, Ph.; Stora, T.; Borcea, C.; Cifmmode \u{a}else \u{a}\fi{}linescu, S.; Daugas, J. M.; Filipescu, D.; Kuti, I.; Franchoo, S.; Gheorghe, I.; Morfouace, P.; Morel, P.; Mrazek, J.; Pietreanu, D.; Sohler, D.; Stefan, I.; ifmmode \mbox{\c{S}}else \c{S}\fi{}uvifmmode \u{a}else \u{a}\fi{}ilifmmode \u{a}else \u{a}\fi{}, R.; Toma, S.; Ur, C. A. in Phys. Rev. C (2019). 100(3) 034306.
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Collectivity of the 2p-2h proton intruder band of ¹¹⁶Sn. Petrache, C. M.; Régis, J.-M.; Andreoiu, C.; Spieker, M.; Michelagnoli, C.; Garrett, P. E.; Astier, A.; Dupont, E.; Garcia, F.; Guo, S.; Häfner, G.; Jolie, J.; Kandzia, F.; Karayonchev, V.; Kim, Y.-H.; Knafla, L.; Köster, U.; Lv, B. F.; Marginean, N.; Mihai, C.; Mutti, P.; Ortner, K.; Porzio, C.; Prill, S.; Saed-Samii, N.; Urban, W.; Vanhoy, J. R.; Whitmore, K.; Wisniewski, J.; Yates, S. W. in Phys. Rev. C (2019). 99(2) 024303.
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Low-lying octupole isovector excitation in ¹⁴⁴Nd. Thürauf, M.; Stoyanov, Ch.; Scheck, M.; Jentschel, M.; Bernards, C.; Blanc, A.; Cooper, N.; De France, G.; Gregor, E. T.; Henrich, C.; Hicks, S. F.; Jolie, J.; Kaleja, O.; Köster, U.; Kröll, T.; Leguillon, R.; Mutti, P.; O'Donnell, D.; Petrache, C. M.; Simpson, G. S.; Smith, J. F.; Soldner, T.; Tezgel, M.; Urban, W.; Vanhoy, J.; Werner, M.; Werner, V.; Zell, K. O.; Zerrouki, T. in Phys. Rev. C (2019). 99(1) 011304.
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On the imprecisions that may be induced when applying the Blaugrund approximation for the analysis of Doppler-shift attenuation lifetime measurements. Petkov, P.; Müller-Gatermann, C. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2019). 915 40 - 46.
It is shown that the Blaugrund approximation could have led to some imprecise lifetime determinations in the past which used the Doppler-shift attenuation method (DSAM). Comparison with Monte Carlo simulations of the slowing-down process show that there is not an easy way to judge using them on the reliability of old data.
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Identification of high-spin proton configurations in ¹³⁶Ba and ¹³⁷Ba. Kaya, L.; Vogt, A.; Reiter, P.; Müller-Gatermann, C.; Gargano, A.; Coraggio, L.; Itaco, N.; Blazhev, A.; Arnswald, K.; Bazzacco, D.; Birkenbach, B.; Bracco, A.; Bruyneel, B.; Corradi, L.; Crespi, F. C. L.; de Angelis, G.; Droste, M.; Eberth, J.; Farnea, E.; Fioretto, E.; Fransen, C.; Gadea, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hadyńska-Klęk, K.; Hess, H.; Hetzenegger, R.; Hirsch, R.; John, P. R.; Jolie, J.; Jungclaus, A.; Korten, W.; Leoni, S.; Lewandowski, L.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Napoli, D.; Podolyák, Zs.; Pollarolo, G.; Recchia, F.; Rosiak, D.; Saed-Samii, N.; Şahin, E.; Siciliano, M.; Scarlassara, F.; Seidlitz, M.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Szpak, B.; Ur, C.; Valiente-Dobón, J. J.; Weinert, M.; Wolf, K.; Zell, K. O. in Phys. Rev. C (2019). 99(1) 014301.
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A new dedicated plunger device for the GALILEO γ-ray detector array. Müller-Gatermann, C.; von Spee, F.; Goasduff, A.; Bazzacco, D.; Beckers, M.; Braunroth, T.; Boso, A.; Cocconi, P.; de Angelis, G.; Dewald, A.; Fransen, C.; Goldkuhle, A.; Gottardo, A.; Gozzelino, A.; Hadyńska-Klęk, K.; Jawroski, G.; John, P.R.; Jolie, J.; Lenzi, S.M.; Litzinger, J.; Menegazzo, R.; Mengoni, D.; Napoli, D.R.; Recchia, F.; Siciliano, M.; Testov, D.; Thiel, S.; Valiente-Dobón, J.J.; Zell, K.O. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2019). 920 95--99.
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Lifetime of the 15/2⁻₁ state in ¹³⁵Te. Simpson, G; Regis, J M; Bettermann, L; Genevey, J; Jolie, J; Köster, U; Materna, T; Malkiewicz, T; Muraz, J-F; Pinston, J A; Roussiere, B; Thiamova, G in Journal of Physics G: Nuclear and Particle Physics (2019). 46(6) 065108.
The lifetime of the state of 135Te has been measured to be τ = 809(22) ps, corresponding to a reduced transition rate of =6.6(2) W.u. The experiment was performed at the focal point of the Lohengrin spectrometer and μs-delayed γ rays from mass-selected A = 135 ions were detected by four LaBr3(Ce) scintillators. This allowed the fast-timing technique to be used to access lifetimes in the 10s-of-ps to ns time region. The value is typical of a vibrational transition, despite 135Te possessing only one valence neutron and two valence protons. Shell model calculations performed with the state-of-the-art effective interaction predict a B(E2) value close to the experimental one and show that contributions from the π(g 7/2, d 5/2)νf 7/2 couplings are coherent.
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Evidence of octupole-phonons at high spin in 207Pb. Ralet, D.; Cl{{é}}ment, E.; Georgiev, G.; Stuchbery, A.E.; Rejmund, M.; Isacker, P. Van; de France, G.; Lemasson, A.; Ljungvall, J.; Michelagnoli, C.; Navin, A.; Balabanski, D.L.; Atanasova, L.; Blazhev, A.; Bocchi, G.; Carroll, R.; Dudouet, J.; Dupont, E.; Fornal, B.; Franchoo, S.; Fransen, C.; Müller-Gatermann, C.; Goasduff, A.; Gadea, A.; John, P.R.; Kocheva, D.; Konstantinopoulos, T.; Korichi, A.; Kusoglu, A.; Lenzi, S.M.; Leoni, S.; Lozeva, R.; Maj, A.; Perez, R.; Pietralla, N.; Shand, C.; Stezowski, O.; Wilmsen, D.; Yordanov, D.; Barrientos, D.; Bednarczyk, P.; Birkenbach, B.; Boston, A.J.; Boston, H.C.; Burrows, I.; Cederwall, B.; Ciemala, M.; Collado, J.; Crespi, F.; Cullen, D.; Eberth, H.J.; Goupil, J.; Harkness, L.; Hess, H.; Jungclaus, A.; Korten, W.; Labiche, M.; Menegazzo, R.; Mengoni, D.; Million, B.; Nyberg, J.; Podoly{{á}}k, Zs.; Pullia, A.; Arn{{é}}s, B. Quintana; Recchia, F.; Reiter, P.; Saillant, F.; Salsac, M.D.; Sanchis, E.; Theisen, C.; Dobon, J.J. Valiente; Wieland, O. in Physics Letters B (2019). 797 134797.
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High-resolution study of the Gamow-Teller (GT-) strength in the ⁶⁴Zn(³He,t)⁶⁴Ga reaction. Diel, F.; Fujita, Y.; Fujita, H.; Cappuzzello, F.; Ganioğlu, E.; Grewe, E.-W.; Hashimoto, T.; Hatanaka, K.; Honma, M.; Itoh, T.; Jolie, J.; Liu, Bin; Otsuka, T.; Takahisa, K.; Susoy, G.; Rubio, B.; Tamii, A. in Phys. Rev. C (2019). 99(5) 054322.
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Valence-shell dependence of the pygmy dipole resonance: E1 strength difference in Cr-50,Cr-54. Ries, P. C.; Pai, H.; Beck, T.; Beller, J.; Bhike, M.; Derya, V; Gayer, U.; Isaak, J.; Loeher, B.; Krishichayan,; Mertes, L.; Pietralla, N.; Romig, C.; Savran, D.; Schilling, M.; Tornow, W.; Typel, S.; Werner, V; Wilhelmy, J.; Zilges, A.; Zweidinger, M. in Phys. Rev. C (2019). 100(2)
Background: The low-lying electric dipole strength provides insights into the parameters of the nuclear equation of state via its connection with the pygmy dipole resonance and nuclear neutron skin thickness. Purpose: The aim was to complement the systematic of the pygmy dipole resonance and first study its behavior across the N = 28 neutron shell closure. Methods: Photon-scattering cross sections of states of Cr-50,Cr-54 were measured up to an excitation energy of 9.7 MeV via the nuclear resonance fluorescence method using gamma-ray beams from bremsstrahlung and Compton backscattering. Results: Transitions strengths, spin and parity quantum number, and average branching ratios for 55 excited states, 44 of which were observed for the first time, were determined. The comparison between the total observed strengths of the isotopes Cr-50,Cr-52,Cr-54 shows a significant increase above the shell closure. Conclusions: The evolution of the pygmy dipole resonance is heavily influenced by the shell structure.
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Evolution of deformation in neutron-rich Ba isotopes up to A=150. Lică, R.; Benzoni, G.; Rodríguez, T. R.; Borge, M. J. G.; Fraile, L. M.; Mach, H.; Morales, A. I.; Madurga, M.; Sotty, C. O.; Vedia, V.; De Witte, H.; Benito, J.; Bernard, R. N.; Berry, T.; Bracco, A.; Camera, F.; Ceruti, S.; Charviakova, V.; Cieplicka-Oryńczak, N.; Costache, C.; Crespi, F. C. L.; Creswell, J.; Fernandez-Martínez, G.; Fynbo, H.; Greenlees, P. T.; Homm, I.; Huyse, M.; Jolie, J.; Karayonchev, V.; Köster, U.; Konki, J.; Kröll, T.; Kurcewicz, J.; Kurtukian-Nieto, T.; Lazarus, I.; Lund, M. V.; Mărginean, N.; Mărginean, R.; Mihai, C.; Mihai, R. E.; Negret, A.; Orduz, A.; Patyk, Z.; Pascu, S.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Regis, J. M.; Robledo, L. M.; Rotaru, F.; Saed-Samii, N.; Sánchez-Tembleque, V.; Stanoiu, M.; Tengblad, O.; Thuerauf, M.; Turturica, A.; Van Duppen, P.; Warr, N. in Phys. Rev. C (2018). 97(2) 024305.
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Archaeometry at the PGAA facility of MLZ - Prompt gamma-ray neutron activation analysis and neutron tomography. Kluge, E. J.; Stieghorst, C.; Wagner, F.E.; Gebhard, R.; Revay, Zs.; Jolie, J. in Journal of Archaeological Science: Reports (2018). 20 303--306.
Instrumental neutron techniques such as Prompt Gamma-ray Activation Analysis and Neutron Tomography and their combination, are effective methods to obtain chemical compositions with good detection limits and visualize internal structures within a sample. As non-destructive analysis methods, they are especially suitable for the investigation of cultural heritage objects and are therefore attractive for the field of archaeometry. This article reports on the investigation of two ring-like Celtic burial gifts from the Bavarian region using these methods. In contrast to our initial resumption, the two rings were not made in the same way. Our results clearly show completely different compositions and internal structures.
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High-resolution (p,t) study of low-spin states in Pu-240: Octupole excitations, alpha clustering, and other structure features. Spieker, M.; Pascu, S.; Bucurescu, D.; Shneidman, T. M.; Faestermann, T.; Hertenberger, R.; Wirth, H-F; {Zamfir, V}; Zilges, A. in Phys. Rev. C (2018). 97(6)
Background: Many nuclear-structure features have been observed in actinides in recent decades. In particular, the octupole degree of freedom has been discussed lately after the successful measurement of the B(E3; 0(1)(+) -> 3(1)(-)) reduced transition strength in Ra-224. Recent results stemming from gamma-spectroscopy experiments and highresolution (p, t) experiments suggested that strong octupole correlations might be observed for some positiveparity states of actinide nuclei. Purpose: This work completes a series of (p, t) experiments on actinide nuclei by adding the data on Pu-240. The (p, t) experiments allow us to study low-spin states up to J(pi) = 6(+). Besides two-nucleon transfer cross sections, spin and parity can be assigned to excited states by measuring angular distributions, and several rotational bands are recognized based on these assignments. Methods: A high-resolution (p, t) experiment at E-p = 24 MeV was performed to populate low-spin states in the actinide nucleus Pu-240. The Q3D magnetic spectrograph of the Maier-Leibnitz Laboratory (MLL) in Munich (Germany) was used to identify the ejected tritons via dE/E particle identification with its focal-plane detection system. Angular distributions were measured at nine different Q3D angles to assign spin and parity to the excited states based on a comparison with coupled-channel distorted-wave Born approximation calculations. Results: In total, 209 states have been excited in Pu-240 up to an excitation energy of 3 MeV. Many previously known states have also been observed and their spin-parity assignments were confirmed. However, many of the populated states have been seen for the first time, e.g., 15 new and firmly assigned J(pi) = 0(+) states. In addition, all low-spin one-octupole phonon excitations, i.e., K-pi = 0(-), 1(-), 2(-), 3(-), could be observed and a new candidate for the K = 3 projection is proposed. Furthermore, the double-octupole or a-cluster structure of the 0+2 state in Pu-240 has been studied in more detail. It is shown that the 0+2 state in Th-230 has a distinctly different structure. In addition, strongly excited 1-states have been observed at 1.5 and 1.8 MeV in Pu-240. The present study suggests that similar states might be observed in Th-230. Conclusions: At least two different and distinct structures for J(pi) = 0(+) states are present in the actinides. These are pairing states and states with enhanced octupole correlations. We have shown that it is crucial to consider negative-parity single-particle states being admixed to some K-pi = 0(2)(+) rotational bands to understand the alpha-decay hindrance factors and enhanced E1-decay rates. Based on our analysis, we have identified the double-octupole or alpha-cluster K-pi = 0(+) candidates from Ra-224 to Pu-240.
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Spins and electromagnetic moments of ¹⁰¹⁻¹⁰⁹Cd. Yordanov, D. T.; Balabanski, D. L.; Bissell, M. L.; Blaum, K.; Blazhev, A.; Budinčević, I.; Frömmgen, N.; Geppert, Ch.; Grawe, H.; Hammen, M.; Kreim, K.; Neugart, R.; Neyens, G.; Nörtershäuser, W. in Phys. Rev. C (2018). 98(1) 011303.
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Enhanced Quadrupole and Octupole Strength in Doubly Magic ¹³²Sn. Rosiak, D.; Seidlitz, M.; Reiter, P.; Naïdja, H.; Tsunoda, Y.; Togashi, T.; Nowacki, F.; Otsuka, T.; Colò, G.; Arnswald, K.; Berry, T.; Blazhev, A.; Borge, M. J. G.; Cederkäll, J.; Cox, D. M.; De Witte, H.; Gaffney, L. P.; Henrich, C.; Hirsch, R.; Huyse, M.; Illana, A.; Johnston, K.; Kaya, L.; Kröll, Th.; Benito, M. L. Lozano; Ojala, J.; Pakarinen, J.; Queiser, M.; Rainovski, G.; Rodriguez, J. A.; Siebeck, B.; Siesling, E.; Snäll, J.; Van Duppen, P.; Vogt, A.; von Schmid, M.; Warr, N.; Wenander, F.; Zell, K. O. in Phys. Rev. Lett. (2018). 121(25) 252501.
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High-spin structure in the transitional nucleus 131Xe: Competitive neutron and proton alignment in the vicinity of the N=82 shell closure. Kaya, L.; Vogt, A.; Reiter, P.; Siciliano, M.; Birkenbach, B.; Blazhev, A.; Coraggio, L.; Teruya, E.; Yoshinaga, N.; Higashiyama, K.; Arnswald, K.; Bazzacco, D.; Bracco, A.; Bruyneel, B.; Corradi, L.; Crespi, F. C. L.; de Angelis, G.; Eberth, J.; Farnea, E.; Fioretto, E.; Fransen, C.; Fu, B.; Gadea, A.; Gargano, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hadyńska-Klęk, K.; Hess, H.; Hetzenegger, R.; Hirsch, R.; Itaco, N.; John, P. R.; Jolie, J.; Jungclaus, A.; Korten, W.; Leoni, S.; Lewandowski, L.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Müller-Gatermann, C.; Napoli, D.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Queiser, M.; Recchia, F.; Rosiak, D.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Schneiders, D.; Seidlitz, M.; Siebeck, B.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szilner, S.; Szpak, B.; Ur, C.; Valiente-Dobón, J. J.; Wolf, K.; Zell, K. O. in Phys. Rev. C (2018). 98(1) 014309.
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β decays of the heaviest N=Z-1 nuclei and proton instability of 97In. Park, J.; Krücken, R.; Lubos, D.; Gernhäuser, R.; Lewitowicz, M.; Nishimura, S.; Ahn, D. S.; Baba, H.; Blank, B.; Blazhev, A.; Boutachkov, P.; Browne, F.; CCfielikovicćfi, I.; de France, G.; Doornenbal, P.; Faestermann, T.; Fang, Y.; Fukuda, N.; Giovinazzo, J.; Goel, N.; Górska, M.; Grawe, H.; Ilieva, S.; Inabe, N.; Isobe, T.; Jungclaus, A.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Lorusso, G.; Moschner, K.; Murai, D.; Nishizuka, I.; Patel, Z.; Rajabali, M. M.; Rice, S.; Sakurai, H.; Schaffner, H.; Shimizu, Y.; Sinclair, L.; Söderström, P.-A.; Steiger, K.; Sumikama, T.; Suzuki, H.; Takeda, H.; Wang, Z.; Watanabe, H.; Wu, J.; Xu, Z. Y. in Phys. Rev. C (2018). 97(5) 051301.
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Transition probabilities in neutron-rich 80,82Se and the role of the νg9/2 orbital. Litzinger, J.; Blazhev, A.; Dewald, A.; Didierjean, F.; Duchêne, G.; Fransen, C.; Lozeva, R.; Verney, D.; de Angelis, G.; Bazzacco, D.; Birkenbach, B.; Bottoni, S.; Bracco, A.; Braunroth, T.; Cederwall, B.; Corradi, L.; Crespi, F. C. L.; Désesquelles, P.; Eberth, J.; Ellinger, E.; Farnea, E.; Fioretto, E.; Gernhäuser, R.; Goasduff, A.; Görgen, A.; Gottardo, A.; Grebosz, J.; Hackstein, M.; Hess, H.; Ibrahim, F.; Jolie, J.; Jungclaus, A.; Kolos, K.; Korten, W.; Leoni, S.; Lunardi, S.; Maj, A.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatovic, T.; Million, B.; Möller, O.; Modamio, V.; Montagnoli, G.; Montanari, D.; Morales, A. I.; Napoli, D. R.; Niikura, M.; Pietralla, N.; Pollarolo, G.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Rosso, D.; Sahin, E.; Salsac, M. D.; Scarlassara, F.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Theisen, Ch.; Valiente-Dobón, J. J.; Vandone, V.; Vogt, A. in Phys. Rev. C (2018). 97(4) 044323.
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Millisecond 23/2+ isomers in the N=79 isotones Xe-133 and Ba-135. Kaya, L.; Vogt, A.; Reiter, P.; Müller-Gatermann, C.; Siciliano, M.; Coraggio, L.; Itaco, N.; Gargano, A.; Arnswald, K.; Bazzacco, D.; Birkenbach, B.; Blazhev, A.; Bracco, A.; Bruyneel, B.; Corradi, L.; Crespi, F. C. L.; de Angelis, G.; Droste, M.; Eberth, J.; Farnea, E.; Fioretto, E.; Fransen, C.; Gadea, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hadyńska-Klęk, K.; Hess, H.; Hetzenegger, R.; Hirsch, R.; John, P. R.; Jolie, J.; Jungclaus, A.; Korten, W.; Leoni, S.; Lewandowski, L.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Napoli, D.; Podolyák, Zs.; Pollarolo, G.; Recchia, F.; Rosiak, D.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Seidlitz, M.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Szpak, B.; Ur, C.; Valiente-Dobón, J. J.; Weinert, M.; Wolf, K.; Zell, K. O. in Phys. Rev. C (2018). 98(5) 054312.
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Study of isomeric states in 198,200,202,206 Pb and 206 Hg populated in fragmentation reactions. Lalović, N; Rudolph, D; Podolyák, Zs; Sarmiento, L G; Simpson, E C; Alexander, T; Cortés, M L; Gerl, J; Golubev, P; Ameil, F; Arici, T; Bauer, Ch; Bazzacco, D; Bentley, M A; Boutachkov, P; Bowry, M; Fahlander, C; Gadea, A; Gellanki, J; Givechev, A; Goel, N; Górska, M; Gottardo, A; Gregor, E; Guastalla, G; Habermann, T; Hackstein, M; Jungclaus, A; Kojouharov, I; Kumar, R; Kurz, N; Lettmann, M; Lizarazo, C; Louchart, C; Merchán, E; Michelagnoli, C; Moeller, Th; Moschner, K; Patel, Z; Pietralla, N; Pietri, S; Ralet, D; Reese, M; Regan, P H; Reiter, P; Schaffner, H; Singh, P; Stahl, C; Stegmann, R; Stezowski, O; Taprogge, J; Thöle, P; Wendt, A; Wieland, O; Wilson, E; Wood, R; Wollersheim, H-J; Birkenbach, B; Bruyneel, B; Burrows, I; Clément, E; Désesquelles, P; Domingo-Pardo, C; Eberth, J; González, V; Hess, H; Jolie, J; Judson, D S; Menegazzo, R; Mengoni, D; Napoli, D R; Pullia, A; Quintana, B; Rainovski, G; Salsac, M D; Sanchis, E; Simpson, J; Dóbon, J J Valiente; Collaboration, the AGATA in Journal of Physics G: Nuclear and Particle Physics (2018). 45(3) 035105.
Isomeric states in isotopes in the vicinity of doubly-magic 208 Pb were populated following reactions of a relativistic 208 Pb primary beam impinging on a 9 Be fragmentation target. Secondary beams of 198,200,202,206 Pb and 206 Hg were isotopically separated and implanted in a passive stopper positioned in the focal plane of the GSI Fragment Separator. Delayed γ rays were detected with the Advanced Gamma Tracking Array (AGATA). Decay schemes were re-evaluated and interpreted with shell-model calculations. The momentum-dependent population of isomeric states in the two-nucleon hole nuclei 206 Pb/ 206 Hg was found to differ from the population of multi neutron-hole isomeric states in 198,200,202 Pb.
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Structure of even-even cadmium isotopes from the beyond-mean-field interacting boson model. Nomura, K.; Jolie, J. in Phys. Rev. C (2018). 98(2) 024303.
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Low-lying electromagnetic transition strengths in 180Pt. Müller-Gatermann, C.; Dewald, A.; Fransen, C.; Braunroth, T.; Jolie, J.; Litzinger, J.; Régis, J. M.; von Spee, F.; Warr, N.; Zell, K. O.; Grahn, T.; Greenlees, P. T.; Hauschild, K.; Jakobsson, U.; Julin, R.; Juutinen, S.; Ketelhut, S.; Nieminen, P.; Nyman, M.; Peura, P.; Rahkila, P.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Scholey, C.; Sorri, J.; Stolze, S.; Uusitalo, J.; Petkov, P. in Phys. Rev. C (2018). 97(2) 024336.
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Structure of Be-13 studied in proton knockout from B-14. Ribeiro, G.; Nacher, E.; Tengblad, O.; Diaz Fernandez, P.; Aksyutina, Y.; Alvarez-Pol, H.; Atar, L.; Aumann, T.; Avdeichikov, V; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boillos, J. M.; Boretzky, K.; Borge, M. J. G.; Caamano, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkall, J.; Chartier, M.; Chulkov, L.; Cortina-Gil, D.; Cravo, E.; Crespo, R.; Pramanik, U. Datta; Dillmann, I; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhaeuser, R.; Golubev, P.; Goebel, K.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Heinz, A.; Henriques, A.; Holl, M.; Hufnagel, A.; Ignatov, A.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Kurz, N.; Kroell, T.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lindberg, S.; Machado, J.; Marganiec, J.; Movsesyan, A.; Nilsson, T.; Nociforo, C.; Panin, V; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Reifarth, R.; Rigollet, C.; Riisager, K.; Rossi, D.; Roeder, M.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Syndikus, I; Taylor, J. T.; Thies, R.; Velho, P.; Wagner, A.; Wamers, F.; Vandebrouck, M.; Weick, H.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; {Zhukov, V}; Zilges, A.; Zuber, K.; Collaboration, R3B in Phys. Rev. C (2018). 98(2)
The neutron-unbound isotope Be-13 has been studied in several experiments using different reactions, different projectile energies, and different experimental setups. There is, however, no real consensus in the interpretation of the data, in particular concerning the structure of the low-lying excited states. Gathering new experimental information, which may reveal the Be-13 structure, is a challenge, particularly in light of its bridging role between Be-12, where the N = 8 neutron shell breaks down, and the Borromean halo nucleus Be-14. The purpose of the present study is to investigate the role of bound excited states in the reaction product Be-12 after proton knockout from B-14, by measuring coincidences between Be-12, neutrons, and gamma rays originating from de-excitation of states fed by neutron decay of Be-13. The Be-13 isotopes were produced in proton knockout from a 400 MeV/nucleon B-14 beam impinging on a CH2 target. The Be-12-n relative-energy spectrum d sigma/dE(fn) was obtained from coincidences between Be-12(g.s.) and a neutron, and also as threefold coincidences by adding gamma rays, from the de-excitation of excited states in Be-12. Neutron decay from the first 5/2(+) state in Be-13 to the 2(+) state in Be-12 at 2.11 MeV is confirmed. An energy independence of the proton-knockout mechanism is found from a comparison with data taken with a 35 MeV/nucleon B-14 beam. A low-lying p-wave resonance in Be-13(1/2(-)) is confirmed by comparing proton- and neutron-knockout data from B-14 and Be-14.
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Lifetime measurements with improved precision in S-30,S-32 and possible influence of large-scale clustering on the appearance of strongly deformed states (vol 96, 034326, 2017). Petkov, P.; Mueller-Gatermann, C.; Dewald, A.; Blazhev, A.; Fransen, C.; Jolie, J.; Scholz, P.; Zell, K. O.; Zilges, A. in Phys. Rev. C (2018). 98(1)
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Strong Neutron Pairing in core+4n Nuclei. Revel, A.; Marques, F. M.; Sorlin, O.; Aumann, T.; Caesar, C.; Holl, M.; Panin, V.; Vandebrouck, M.; Wamers, F.; Alvarez-Pol, H.; Atar, L.; Avdeichikov, V.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boillos, J. M.; Boretzky, K.; Borge, M. J. G.; Caamano, M.; Casarejos, E.; Catford, W. N.; Cederkall, J.; Chartier, M.; Chulkov, L.; Cortina-Gil, D.; Cravo, E.; Crespo, R.; Pramanik, U. Datta; Diaz Fernandez, P.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Galaviz, D.; Geissel, H.; Gernhaeuser, R.; Golubev, P.; Goebel, K.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Heinz, A.; Henriques, A.; Ignatov, A.; Johansson, H. T.; Jonson, B.; Kahlbow, J.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knyazev, A.; Kroell, T.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lindberg, S.; Machado, J.; Marganiec, J.; Movsesyan, A.; Nacher, E.; Najafi, M.; Nilsson, T.; Nociforo, C.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Reifarth, R.; Ribeiro, G.; Rigollet, C.; Roeder, M.; Rossi, D.; Savran, D.; Scheit, H.; Simon, H.; Syndikus, I.; Taylor, J. T.; Tengblad, O.; Thies, R.; Velho, Y. Togano P.; Volkov, V.; Wagner, A.; Weick, H.; Wheldon, C.; Wilson, G.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M.; Zilges, A.; Zuber, K.; Collaboration, R3B in Physical Review Letters (2018). 120(15)
The emission of neutron pairs from the neutron-rich N = 12 isotones C-18 and O-20 has been studied by high-energy nucleon knockout from N-19 and O-21 secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay N-19(-1p)18C{*}-> C-16 + n + n is clearly dominated by direct pair emission. The two- neutron correlation strength, the largest ever observed, suggests the predominance of a C-14 core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay O-21(-1n)O-20{*}-> O-18 + n + n, attributed to its formation through the knockout of a deeply bound neutron that breaks the O-16 core and reduces the number of pairs.
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Quasifree (p, 2p) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength. Atar, L.; Paschalis, S.; Barbieri, C.; Bertulani, C. A.; Diaz Fernandez, P.; Holl, M.; Najafi, M. A.; Panin, V.; Alvarez-Pol, H.; Aumann, T.; Avdeichikov, V.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Boillos, J. M.; Boretzky, K.; Borge, M. J. G.; Caamano, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkall, J.; Chartier, M.; Chulkov, L.; Cortina-Gil, D.; Cravo, E.; Crespo, R.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Galaviz Redondo, D.; Geissel, H.; Gernhaeuser, R.; Golubev, P.; Goebel, K.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Heinz, A.; Henriques, A.; Hufnagel, A.; Ignatov, A.; Johansson, H. T.; Jonson, B.; Kahlbow, J.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knyazev, A.; Kroell, T.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lindberg, S.; Machado, J.; Marganiec-Galazka, J.; Movsesyan, A.; Nacher, E.; Nikolskii, E. Y.; Nilsson, T.; Nociforo, C.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Reifarth, R.; Ribeiro, G.; Rigollet, C.; Rossi, D. M.; Roeder, M.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Syndikus, I.; Taylor, J. T.; Tengblad, O.; Thies, R.; Togano, Y.; Vandebrouck, M.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Wheldon, C.; Wilson, G. L.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M.; Zilges, A.; Zuber, K.; Collaboration, R3B in Physical Review Letters (2018). 120(5)
Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the (RB)-B-3/LAND setup with incident beam energies in the range of 300-450 MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type O-A(p,2p)NA-1 have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.
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Multi-messenger investigation of the Pygmy Dipole Resonance in Ce-140. Savran, D.; Derya, V.; Bagchi, S.; Endres, J.; Harakeh, M. N.; Isaak, J.; Kalantar-Nayestanaki, N.; Lanza, E. G.; Loeher, B.; Najafi, A.; Pascu, S.; Pickstone, S. G.; Pietralla, N.; Ponomarev, V. Yu.; Rigollet, C.; Romig, C.; Spieker, M.; Vitturi, A.; Zilges, A. in Physics Letters B (2018). 786 16-20.
We report on the first (p, p'gamma) experiments at E-p = 80 MeV to investigate the Pygmy Dipole Resonance (PDR) in the semi-magic nucleus Ce-140. This experiment is the latest in a series of experiments to investigate the PDR with different complementary probes to provide a multi-messenger data set on the properties of the PDR in Ce-140. In addition, calculations within the Quasi-particle Phonon Model (QPM) have been performed. Cross sections have been calculated for proton- as well as alpha-scattering reactions based on the transition densities obtained from the QPM, not only at the RPA level, but including the full model space of up to 3p-3h configurations. This allows for the first time to compare the calculations to the experimental results on an absolute scale for single excitations. Agreement between QPM and experiment is observed, which proves the high accuracy of the calculated transition densities for individual PDR states. (C) 2018 The Author(s). Published by Elsevier B.V.
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First Accurate Normalization of the beta-delayed alpha Decay of 16N and Implications for the 12C(alpha,gamma)16O Astrophysical Reaction Rate. Kirsebom, O. S.; Tengblad, O.; Lica, R.; Munch, M.; Riisager, K.; Fynbo, H. O. U.; Borge, M. J. G.; Madurga, M.; Marroquin, I.; Andreyev, A. N.; Berry, T. A.; Christensen, E. R.; Fernández, P. D\'{i}az; Doherty, D. T.; Van Duppen, P.; Fraile, L. M.; Gallardo, M. C.; Greenlees, P. T.; Harkness-Brennan, L. J.; Hubbard, N.; Huyse, M.; Jensen, J. H.; Johansson, H.; Jonson, B.; Judson, D. S.; Konki, J.; Lazarus, I.; Lund, M. V.; Marginean, N.; Marginean, R.; Perea, A.; Mihai, C.; Negret, A.; Page, R. D.; Pucknell, V.; Rahkila, P.; Sorlin, O.; Sotty, C.; Swartz, J. A.; S\o{}rensen, H. B.; Törnqvist, H.; Vedia, V.; Warr, N.; De Witte, H. in Phys. Rev. Lett. (2018). 121(14) 142701.
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Investigation of J=1 states and their gamma-decay behavior in Cr-52. Wilhelmy, J.; Brown, A.; Erbacher, P.; Gayer, U.; Isaak, J.; Krishichayan,; Loeher, B.; Muescher, M.; Pai, H.; Pietralla, N.; Ries, P.; Savran, D.; Scholz, P.; Spieker, M.; Tornow, W.; Werner, V; Zilges, A. in Phys. Rev. C (2018). 98(3)
Background: In the A approximate to 50 mass region M1 spin-flip transitions are prominent around 9 MeV. An accumulation of 1(-) states between 5 and 8 MeV generating additional E1 strength, also denoted as pygmy dipole resonance, has been established in many nuclei with neutron excess within the last decade. Purpose: The gamma-decay behavior of J = 1 states has been investigated in an NRF experiment. M1 excitations have been compared to shell model calculations. Methods: J = 1 states were excited by quasi-monoenergetic, linearly polarized gamma-ray beams generated by laser-Compton backscattering at the HI gamma S facility, Durham, NC, USA. Depopulating gamma rays were detected with the multidetector array gamma(3). Results: For eleven beam-energy settings the gamma-decay behavior of dipole states was analyzed by a state-to-state analysis and average gamma-decay branching ratios have been investigated. 34 parity quantum numbers were assigned to J = 1 states. Conclusions: Six 1(-) states and two 1(+) states have been investigated in NRF experiments for the first time. The M1 strength distribution is in good agreement with shell-model calculations.
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The SPEDE spectrometer. Papadakis, P.; Cox, D. M.; O'Neill, G. G.; Borge, M. J. G.; Butler, P. A.; Gaffney, L. P.; Greenlees, P. T.; Herzberg, R. D.; Illana, A.; Joss, D. T.; Konki, J.; Kr{ö}ll, T.; Ojala, J.; Page, R. D.; Rahkila, P.; Ranttila, K.; Thornhill, J.; Tuunanen, J.; Van Duppen, P.; Warr, N.; Pakarinen, J. in The European Physical Journal A (2018). 54(3) 42.
The electron spectrometer, SPEDE, has been developed and will be employed in conjunction with the Miniball spectrometer at the HIE-ISOLDE facility, CERN. SPEDE allows for direct measurement of internal conversion electrons emitted in-flight, without employing magnetic fields to transport or momentum filter the electrons. Together with the Miniball spectrometer, it enables simultaneous observation of {\\($} {\backslash}gamma{\$\)}\($\gamma$\)rays and conversion electrons in Coulomb excitation experiments using radioactive ion beams.
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Evolution of deformation in neutron-rich Ba isotopes up to \($A=150$\). Lica, R.; Benzoni, G.; Rodr\'{i}guez, T. R.; Borge, M. J. G.; Fraile, L. M.; Mach, H.; Morales, A. I.; Madurga, M.; Sotty, C. O.; Vedia, V.; De Witte, H.; Benito, J.; Bernard, R. N.; Berry, T.; Bracco, A.; Camera, F.; Ceruti, S.; Charviakova, V.; Cieplicka-Oryifmmode \acute{n}else {{\'n}}\fi{}czak, N.; Costache, C.; Crespi, F. C. L.; Creswell, J.; Fernandez-Mart\'{i}nez, G.; Fynbo, H.; Greenlees, P. T.; Homm, I.; Huyse, M.; Jolie, J.; Karayonchev, V.; Köster, U.; Konki, J.; Kröll, T.; Kurcewicz, J.; Kurtukian-Nieto, T.; Lazarus, I.; Lund, M. V.; Mifmmode \u{a}else \u{a}\fi{}rginean, N.; Mifmmode \u{a}else \u{a}\fi{}rginean, R.; Mihai, C.; Mihai, R. E.; Negret, A.; Orduz, A.; Patyk, Z.; Pascu, S.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Regis, J. M.; Robledo, L. M.; Rotaru, F.; Saed-Samii, N.; Sánchez-Tembleque, V.; Stanoiu, M.; Tengblad, O.; Thuerauf, M.; Turturica, A.; Van Duppen, P.; Warr, N. in Phys. Rev. C (2018). 97(2) 024305.
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Quasifree (p, pN) scattering of light neutron-rich nuclei near N=14. Diaz Fernandez, P.; Alvarez-Pol, H.; Crespo, R.; Cravo, E.; Atar, L.; Deltuva, A.; Aumann, T.; Avdeichikov, V.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boillos, J. M.; Boretzky, K.; Borge, M. J. G.; Caamano, M.; Cabanelas, P.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkall, J.; Chartier, M.; Chulkov, L. V.; Cortina-Gil, D.; Pramanik, U. Datta; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fernandez-Dominguez, B.; Fraile, L. M.; Freer, M.; Galaviz, D.; Geissel, H.; Gernhaeuser, R.; Golubev, P.; Goebel, K.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Heinz, A.; Henriques, A.; Holl, M.; Hufnagel, A.; Ignatov, A.; Johansson, H. T.; Jonson, B.; Jurciukonis, D.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knyazev, A.; Kroell, T.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lindberg, S.; Machado, J.; Marganiec, J.; Moro, A. M.; Movsesyan, A.; Nacher, E.; Najafi, A.; Nikolskii, E.; Nilsson, T.; Nociforo, C.; Panin, V.; Paschalis, S.; Perea, A.; Petri, M.; Pietras, B.; Pietri, S.; Plag, R.; Reifarth, R.; Ribeiro, G.; Rigollet, C.; Rossi, D.; Roeder, M.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Syndikus, I.; Taylor, J. T.; Tengblad, O.; Thies, R.; Togano, Y.; Vandebrouck, M.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Wheldon, C.; Wilson, G.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M.; Zilges, A.; Zuber, K.; Collaboration, R3B in Phys. Rev. C (2018). 97(2)
Background: For many years, quasifree scattering reactions in direct kinematics have been extensively used to study the structure of stable nuclei, demonstrating the potential of this approach. The (RB)-B-3 collaboration has performed a pilot experiment to study quasifree scattering reactions in inverse kinematics for a stable C-12 beam. The results from that experiment constitute the first quasifree scattering results in inverse and complete kinematics. This technique has lately been extended to exotic beams to investigate the evolution of shell structure, which has attracted much interest due to changes in shell structure if the number of protons or neutrons is varied. Purpose: In this work we investigate for the first time the quasifree scattering reactions (p, pn) and (p, 2p) simultaneously for the same projectile in inverse and complete kinematics for radioactive beams with the aim to study the evolution of single-particle properties from N = 14 to N = 15. Method: The structure of the projectiles O-23, O-22, and N-21 has been studied simultaneously via (p, pn) and (p, 2p) quasifree knockout reactions in complete inverse kinematics, allowing the investigation of proton and neutron structure at the same time. The experimental data were collected at the (RB)-B-3-LAND setup at GSI at beam energies of around 400 MeV/u. Two key observables have been studied to shed light on the structure of those nuclei: the inclusive cross sections and the corresponding momentum distributions. Conclusions: The knockout reactions (p, pn) and (p, 2p) with radioactive beams in inverse kinematics have provided important and complementary information for the study of shell evolution and structure. For the (p, pn) channels, indications of a change in the structure of these nuclei moving from N = 14 to N = 15 have been observed, i.e., from the 0d(5/2) shell to the 1s(1/2). This supports previous observations of a subshell closure at N = 14 for neutron-rich oxygen isotopes and its weakening for the nitrogen isotopes.
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Shape coexistence and collective low-spin states in Sn-112,Sn-114 studied with the (p,p'y) Doppler-shift attenuation coincidence technique. Spieker, M.; Petkov, P.; Litvinova, E.; Mueller-Gatermann, C.; Pickstone, S. G.; Prill, S.; Scholz, P.; Zilges, A. in Phys. Rev. C (2018). 97(5)
Background: The semimagic Sn (Z = 50) isotopes have been subject to many nuclear-structure studies. Signatures of shape coexistence have been observed and attributed to two-proton-two-hole (2p-2h) excitations across the Z = 50 shell closure. In addition, many low-lying nuclear-structure features have been observed which have effectively constrained theoretical models in the past. One example are so-called quadrupole-octupole coupled states (QOC) caused by the coupling of the collective quadrupole and octupole phonons. Purpose: Proton-scattering experiments followed by the coincident spectroscopy of gamma rays have been performed at the Institute for Nuclear Physics of the University of Cologne to excite low-spin states in Sn-112 and Sn-114 to determine their lifetimes and extract reduced transition strengths B(Pi L) Methods: The combined spectroscopy setup SONIC@HORUS has been used to detect the scattered protons and the emitted y rays of excited states in coincidence. The novel (p,p'gamma) Doppler-shift attenuation (DSA) coincidence technique was employed to measure sub-ps nuclear level lifetimes. Results: Seventy-four (74) level lifetimes tau of states with J = 0-6 were determined. In addition, branching ratios were deduced which allowed the investigation of the intruder configuration in both nuclei. Here, sd IBM-2 mixing calculations were added which support the coexistence of the two configurations. Furthermore, members of the expected QOC quintuplet are proposed in Sn-114 for the first time. The 1(-) candidate in Sn-114 fits perfectly into the systematics observed for the other stable Sn isotopes. Conclusions: The E2 transition strengths observed for the low-spin members of the so-called intruder band support the existence of shape coexistence in Sn-112,Sn-114. The collectivity in this configuration is comparable to the one observed in the Pd nuclei, i.e., the 0p-4h nuclei. Strong mixing between the 0(+) states of the normal and intruder configuration might be observed in Sn-114. The general existence of QOC states in Sn-112,Sn-114 is supported by the observation of QOC candidates with J not equal 1.
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A simple procedure for γ-γ lifetime measurements using multi-element fast-timing arrays. Régis, J.-M.; Dannhoff, M.; Jolie, J. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2018). 897 38 - 46.
Abstract The lifetimes of nuclear excited states are important observables in nuclear physics. Their precise measurement is of key importance for developing and testing nuclear models as they are directly linked with the quantum nature of the nuclear system. The γ - γ timing technique represents a direct lifetime determination by means of time-difference measurements between the γ rays which directly feed and decay from a nuclear excited state. Using arrays of very-fast scintillator detectors, picosecond-sensitive time-difference measurements can be performed. We propose to construct a symmetric energy–energy–time cube as is usually done to perform γ - γ coincidence analyses and lifetime determination with high-resolution germanium detectors. By construction, a symmetric mean time-walk characteristics is obtained, that can be precisely determined and used as a single time correction for all the data independently of the detectors. We present the results of timing characteristics measurements of an array with six LaBr 3 (Ce) detectors, as obtained using a 152Eu point γ -ray source. Compared with a single detector pair, the time resolution of the symmetrised time-difference spectra of the array is nearly unaffected.
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The first (53Mn/55Mn) isotopic ratio measurements at the Cologne {FN}-Tandem Accelerator. Schiffer, M.; Spanier, R.; Müller-Gatermann, C.; Herb, S.; Feuerstein, C.; Hackenberg, G.; Marock, M.; Heinze, S.; Stolz, A.; Dewald, A.; Binnie, S. in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (2018). 437 87--92.
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Lifetime determination in 190,192,194,196Hg via γ-γ fast-timing spectroscopy. Esmaylzadeh, A.; Gerhard, L. M.; Karayonchev, V.; Régis, J.-M.; Jolie, J.; Bast, M.; Blazhev, A.; Braunroth, T.; Dannhoff, M.; Dunkel, F.; Fransen, C.; Häfner, G.; Knafla, L.; Ley, M.; Müller-Gatermann, C.; Schomacker, K.; Warr, N.; Zell, K.-O. in Phys. Rev. C (2018). 98(1) 014313.
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Properties of γ-decaying isomers and isomeric ratios in the 100Sn region. Park, J.; Krücken, R.; Lubos, D.; Gernhäuser, R.; Lewitowicz, M.; Nishimura, S.; Ahn, D. S.; Baba, H.; Blank, B.; Blazhev, A.; Boutachkov, P.; Browne, F.; Čeliković, I.; de France, G.; Doornenbal, P.; Faestermann, T.; Fang, Y.; Fukuda, N.; Giovinazzo, J.; Goel, N.; Górska, M.; Grawe, H.; Ilieva, S.; Inabe, N.; Isobe, T.; Jungclaus, A.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Lorusso, G.; Moschner, K.; Murai, D.; Nishizuka, I.; Patel, Z.; Rajabali, M. M.; Rice, S.; Sakurai, H.; Schaffner, H.; Shimizu, Y.; Sinclair, L.; Söderström, P.-A.; Steiger, K.; Sumikama, T.; Suzuki, H.; Takeda, H.; Wang, Z.; Watanabe, H.; Wu, J.; Xu, Z. Y. in Phys. Rev. C (2017). 96(4) 044311.
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Simultaneous investigation of the T = 1( Jπ = 0⁺) and T = 0( Jπ = 9⁺) β decays in ⁷⁰Br. Morales, A. I.; Algora, A.; Rubio, B.; Kaneko, K.; Nishimura, S.; Aguilera, P.; Orrigo, S. E. A.; Molina, F.; de Angelis, G.; Recchia, F.; Kiss, G.; Phong, V. H.; Wu, J.; Nishimura, D.; Oikawa, H.; Goigoux, T.; Giovinazzo, J.; Ascher, P.; Agramunt, J.; Ahn, D. S.; Baba, H.; Blank, B.; Borcea, C.; Boso, A.; Davies, P.; Diel, F.; Dombrádi, Zs.; Doornenbal, P.; Eberth, J.; de France, G.; Fujita, Y.; Fukuda, N.; Ganioglu, E.; Gelletly, W.; Gerbaux, M.; Grévy, S.; Guadilla, V.; Inabe, N.; Isobe, T.; Kojouharov, I.; Korten, W.; Kubo, T.; Kubono, S.; Kurtukián Nieto, T.; Kurz, N.; Lee, J.; Lenzi, S.; Liu, J.; Lokotko, T.; Lubos, D.; Magron, C.; Montaner-Pizá, A.; Napoli, D. R.; Sakurai, H.; Schaffner, H.; Shimizu, Y.; Sidong, C.; Söderström, P.-A.; Sumikama, T.; Suzuki, H.; Takeda, H.; Takei, Y.; Tanaka, M.; Yagi, S. in Phys. Rev. C (2017). 95(6) 064327.
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The role of core excitations in the structure and decay of the 16+ spin-gap isomer in 96Cd. Davies, P.J.; Grawe, H.; Moschner, K.; Blazhev, A.; Wadsworth, R.; Boutachkov, P.; Ameil, F.; Yagi, A.; Baba, H.; Bäck, T.; Dewald, M.; Doornenbal, P.; Faestermann, T.; Gengelbach, A.; Gerl, J.; Gernhäeuser, R.; Go, S.; Górska, M.; Gregor, E.; Isobe, T.; Jenkins, D.G.; Hotaka, H.; Jolie, J.; Kojouharov, I.; Kurz, N.; Lewitowicz, M.; Lorusso, G.; Maier, L.; Merchan, E.; Naqvi, F.; Nishibata, H.; Nishimura, D.; Nishimura, S.; Nowacki, F.; Pietralla, N.; Schaffner, H.; Söderström, P.-A.; Jung, H.S.; Steiger, K.; Sumikama, T.; Taprogge, J.; Thöle, P.; Warr, N.; Watanabe, H.; Werner, V.; Xu, Z.Y.; Yoshinaga, K.; Zhu, Y. in Physics Letters B (2017). 767 474 - 479.
Abstract The first evidence for β-delayed proton emission from the 16+ spin gap isomer in 96Cd is presented. The data were obtained from the Rare Isotope Beam Factory, at the RIKEN Nishina Center, using the BigRIPS spectrometer and the EURICA decay station. βp branching ratios for the ground state and 16+ isomer have been extracted along with more precise lifetimes for these states and the lifetime for the ground state decay of 95Cd. Large scale shell model (LSSM) calculations have been performed and WKB estimates made for ℓ=0,2,4 proton emission from three resonance-like states in 96Ag, that are populated by the β decay of the isomer, and the results compared to the new data. The calculations suggest that ℓ=2 proton emission from the resonance states, which reside ∼5 MeV above the proton separation energy, dominates the proton decay. The results highlight the importance of core-excited wavefunction components for the 16+ state.
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Isomers and high-spin structures in the N=81 isotones 135Xe and 137Ba. Vogt, A.; Birkenbach, B.; Reiter, P.; Blazhev, A.; Siciliano, M.; Hadyńska-Klęk, K.; Valiente-Dobón, J. J.; Wheldon, C.; Teruya, E.; Yoshinaga, N.; Arnswald, K.; Bazzacco, D.; Bowry, M.; Bracco, A.; Bruyneel, B.; Chakrawarthy, R. S.; Chapman, R.; Cline, D.; Corradi, L.; Crespi, F. C. L; Cromaz, M.; de Angelis, G.; Eberth, J.; Fallon, P.; Farnea, E.; Fioretto, E.; Freeman, S. J.; Fu, B.; Gadea, A.; Geibel, K.; Gelletly, W.; Gengelbach, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hayes, A. B.; Hess, H.; Hirsch, R.; Hua, H.; John, P. R.; Jolie, J.; Jungclaus, A.; Kaya, L.; Korten, W.; Lee, I. Y.; Leoni, S.; Lewandowski, L.; Liang, X.; Lunardi, S.; Macchiavelli, A. O.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Müller-Gatermann, C.; Napoli, D.; Pearson, C. J.; Pellegri, L.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Queiser, M.; Radeck, F.; Recchia, F.; Regan, P. H.; Rosiak, D.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Schneiders, D.; Seidlitz, M.; Siebeck, B.; Sletten, G.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szilner, S.; Szpak, B.; Teng, R.; Ur, C.; Vandone, V.; Warner, D. D.; Wiens, A.; Wu, C. Y.; Zell, K. O. in Phys. Rev. C (2017). 95(2) 024316.
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Lifetimes and electromagnetic transition strengths in ¹⁵⁷Dy. Gladnishki, K. A.; Petkov, P.; Möller, O.; Dewald, A.; Jolie, J.; Tonev, D.; Trichkova, M.; Heinze, S.; von Brentano, P.; Bazzacco, D.; Ur, C. A.; Farnea, E.; Axiotis, M.; Lunardi, S.; de Angelis, G.; Napoli, D. R.; Marginean, N.; Martinez, T.; Caprio, M. A.; Rainovski, G. in Phys. Rev. C (2017). 96(2) 024324.
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High-spin structures in 132Xe and 133Xe and evidence for isomers along the N=79 isotones. Vogt, A.; Siciliano, M.; Birkenbach, B.; Reiter, P.; Hadyńska-Klęk, K.; Wheldon, C.; Valiente-Dobón, J. J.; Teruya, E.; Yoshinaga, N.; Arnswald, K.; Bazzacco, D.; Blazhev, A.; Bracco, A.; Bruyneel, B.; Chakrawarthy, R. S.; Chapman, R.; Cline, D.; Corradi, L.; Crespi, F. C. L.; Cromaz, M.; de Angelis, G.; Eberth, J.; Fallon, P.; Farnea, E.; Fioretto, E.; Fransen, C.; Freeman, S. J.; Fu, B.; Gadea, A.; Gelletly, W.; Giaz, A.; Görgen, A.; Gottardo, A.; Hayes, A. B.; Hess, H.; Hetzenegger, R.; Hirsch, R.; Hua, H.; John, P. R.; Jolie, J.; Jungclaus, A.; Karayonchev, V.; Kaya, L.; Korten, W.; Lee, I. Y.; Leoni, S.; Liang, X.; Lunardi, S.; Macchiavelli, A. O.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Müller-Gatermann, C.; Napoli, D.; Pearson, C. J.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Queiser, M.; Recchia, F.; Regan, P. H.; Régis, J.-M.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Seidlitz, M.; Siebeck, B.; Sletten, G.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Szpak, B.; Teng, R.; Ur, C.; Warner, D. D.; Wolf, K.; Wu, C. Y.; Zell, K. O. in Phys. Rev. C (2017). 96(2) 024321.
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A revised B(E2;2⁺₁→ 0⁺₁) value in the semi-magic nucleus ²¹⁰Po. Kocheva, D.; Rainovski, G.; Jolie, J.; Pietralla, N.; Blazhev, A.; Astier, A.; Altenkirch, R.; Ansari, S.; Braunroth, Th.; Cortés, M. L.; Dewald, A.; Diel, F.; Djongolov, M.; Fransen, C.; Gladnishki, K.; Hennig, A.; Karayonchev, V.; Keatings, J. M.; Kluge, E.; Litzinger, J.; Müller-Gatermann, C.; Petkov, P.; Rudigier, M.; Scheck, M.; Scholz, Ph.; Spagnoletti, P.; Spieker, M.; Stahl, C.; Stegmann, R.; Stoyanova, M.; Th{ö}le, P.; Warr, N.; Werner, V.; Witt, W.; Wölk, D.; Zell, K. O.; Van Isacker, P.; Ponomarev, V. Yu. in The European Physical Journal A (2017). 53(9) 175.
A revised B(E2;2⁺₁→ 0⁺₁) value in the semi-magic nucleus ²¹⁰Po
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β decay studies of n-rich Cs isotopes with the ISOLDE Decay Station. Lică, R; Benzoni, G; Morales, A I; Borge, M J G; Fraile, L M; Mach, H; Madurga, M; Sotty, C; Vedia, V; Witte, H De; Benito, J; Berry, T; Blasi, N; Bracco, A; Camera, F; Ceruti, S; Charviakova, V; Cieplicka-Oryńczak, N; Costache, C; Crespi, F C L; Creswell, J; Fernández-Martínez, G; Fynbo, H; Greenlees, P; Homm, I; Huyse, M; Jolie, J; Karayonchev, V; Köster, U; Konki, J; Kröll, T; Kurcewicz, J; Kurtukian-Nieto, T; Lazarus, I; Leoni, S; Lund, M; Marginean, N; Marginean, R; Mihai, C; Mihai, R; Negret, A; Orduz, A; Patyk, Z; Pascu, S; Pucknell, V; Rahkila, P; Regis, J M; Rotaru, F; Saed-Sami, N; Sánchez-Tembleque, V; Stanoiu, M; Tengblad, O; Thuerauf, M; Turturica, A; Duppen, P Van; Warr, N in Journal of Physics G: Nuclear and Particle Physics (2017). 44(5) 054002.
Neutron-rich Ba isotopes are expected to exhibit octupolar correlations, reaching their maximum in isotopes around mass A = 146. The odd- A neutron-rich members of this isotopic chain show typical patterns related to non-axially symmetric shapes, which are however less marked compared to even- A ones, pointing to a major contribution from vibrations. In the present paper we present results from a recent study focused on 148–150 Cs β -decay performed at the ISOLDE Decay Station equipped with fast-timing detectors. A detailed analysis of the measured decay half-lives and decay scheme of 149 Ba is presented, giving a first insight in the structure of this neutron-rich nucleus.
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Erratum: Abrupt shape transition at neutron number N = 60: B(E2) values in ⁹⁴’⁹⁶’⁹⁸Sr from fast γ-γ timing. Régis, J.-M.; Jolie, J.; Saed-Samii, N.; Warr, N.; Pfeiffer, M.; Blanc, A.; Jentschel, M.; Késter, U.; Mutti, P.; Soldner, T.; Simpson, G. S.; Drouet, F.; Vancraeyenest, A.; de France, G.; Clément, E.; Stezowski, O.; Ur, C. A.; Urban, W.; Regan, P. H.; Podolyák, Zs.; Larijani, C.; Townsley, C.; Carroll, R.; Wilson, E.; Fraile, L. M.; Mach, H.; Paziy, V.; Olaizola, B.; Vedia, V.; Bruce, A. M.; Roberts, O. J.; Smith, J. F.; Scheck, M.; Kröll, T.; Hartig, A.-L.; Ignatov, A.; Ilieva, S.; Lalkovski, S.; Korten, W.; Marginean, N.; Otsuka, T.; Shimizu, N.; Togashi, T.; Tsunoda, Y. in Phys. Rev. C (2017). 95(6) 069902.
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Search for the 73Ga ground-state doublet splitting in the β decay of 73Zn. Vedia, V.; Paziy, V.; Fraile, L. M.; Mach, H.; Walters, W. B.; Aprahamian, A.; Bernards, C.; Briz, J. A.; Bucher, B.; Chiara, C. J.; Dlouhý, Z.; Gheorghe, I.; Ghiţă, D.; Hoff, P.; Jolie, J.; Köster, U.; Kurcewicz, W.; Lică, R.; Mărginean, N.; Mărginean, R.; Olaizola, B.; Régis, J.-M.; Rudigier, M.; Sava, T.; Simpson, G. S.; Stănoiu, M.; Stroe, L. in Phys. Rev. C (2017). 96(3) 034311.
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Shell-model-based deformation analysis of light cadmium isotopes. Schmidt, T.; Heyde, K. L. G.; Blazhev, A.; Jolie, J. in Phys. Rev. C (2017). 96(1) 014302.
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Combining γ-ray and particle spectroscopy with SONIC@HORUS. Pickstone, Simon G.; Weinert, Michael; Färber, Michelle; Heim, Felix; Hoemann, Elena; Mayer, Jan; Müscher, Miriam; Prill, Sarah; Scholz, Philipp; Spieker, Mark; Vielmetter, Vera; Wilhelmy, Julius; Zilges, Andreas in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2017). 875 104 - 110.
Abstract The particle spectrometer SONIC for particle-γ coincidence measurements was commissioned at the Institute for Nuclear Physics in Cologne, Germany. SONIC consists of up to 12 silicon ΔE-E telescopes with a total solid angle coverage of 9%, and will complement HORUS, a γ-ray spectrometer with 14 HPGe detectors. The combined setup SONIC@HORUS is used to investigate the γ-decay behaviour of low-spin states up to the neutron separation threshold excited by light-ion inelastic scattering and transfer reactions using beams provided by a 10 MV FN Tandem accelerator. The particle-γ coincidence method will be presented using data from a 92Mo(p,p’γ) experiment. In a 119Sn(d,X) experiment, excellent particle identification has been achieved because of the good energy resolution of the silicon detectors of approximately 20 keV. Due to the non-negligible momentum transfer in the reaction, a Doppler correction of the detected γ-ray energy has to be performed, using the additional information from measuring the ejectile energy and direction. The high sensitivity of the setup is demonstrated by the results from a 94Mo(p,p’γ) experiment, where small γ-decay branching ratios have been deduced.
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Triaxiality of neutron-rich ⁸⁴’⁸⁶’⁸⁸Ge from low-energy nuclear spectra. Lettmann, M.; Werner, V.; Pietralla, N.; Doornenbal, P.; Obertelli, A.; Rodrìguez, T. R.; Sieja, K.; Authelet, G.; Baba, H.; Calvet, D.; Château, F.; Chen, S.; Corsi, A.; Delbart, A.; Gheller, J.-M.; Giganon, A.; Gillibert, A.; Lapoux, V.; Motobayashi, T.; Niikura, M.; Paul, N.; Roussé, J.-Y.; Sakurai, H.; Santamaria, C.; Steppenbeck, D.; Taniuchi, R.; Uesaka, T.; Ando, T.; Arici, T.; Blazhev, A.; Browne, F.; Bruce, A.; Caroll, R. J.; Chung, L. X.; Cortés, M. L.; Dewald, M.; Ding, B.; Flavigny, F.; Franchoo, S.; Górska, M.; Gottardo, A.; Jungclaus, A.; Lee, J.; Linh, B. D.; Liu, J.; Liu, Z.; Lizarazo, C.; Momiyama, S.; Moschner, K.; Nagamine, S.; Nakatsuka, N.; Nita, C.; Nobs, C. R.; Olivier, L.; Patel, Z.; Podolyák, Zs.; Rudigier, M.; Saito, T.; Shand, C.; Söderström, P.-A.; Stefan, I.; Vaquero, V.; Wimmer, K.; Xu, Z. in Phys. Rev. C (2017). 96(1) 011301.
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Shape Evolution in Neutron-Rich Krypton Isotopes Beyond N=60: First Spectroscopy of ⁹⁸'¹⁰⁰Kr. Flavigny, F.; Doornenbal, P.; Obertelli, A.; Delaroche, J.-P.; Girod, M.; Libert, J.; Rodriguez, T. R.; Authelet, G.; Baba, H.; Calvet, D.; Château, F.; Chen, S.; Corsi, A.; Delbart, A.; Gheller, J.-M.; Giganon, A.; Gillibert, A.; Lapoux, V.; Motobayashi, T.; Niikura, M.; Paul, N.; Roussé, J.-Y.; Sakurai, H.; Santamaria, C.; Steppenbeck, D.; Taniuchi, R.; Uesaka, T.; Ando, T.; Arici, T.; Blazhev, A.; Browne, F.; Bruce, A.; Carroll, R.; Chung, L. X.; Cortés, M. L.; Dewald, M.; Ding, B.; Franchoo, S.; Górska, M.; Gottardo, A.; Jungclaus, A.; Lee, J.; Lettmann, M.; Linh, B. D.; Liu, J.; Liu, Z.; Lizarazo, C.; Momiyama, S.; Moschner, K.; Nagamine, S.; Nakatsuka, N.; Nita, C.; Nobs, C. R.; Olivier, L.; Orlandi, R.; Patel, Z.; Podolyák, Zs.; Rudigier, M.; Saito, T.; Shand, C.; Söderström, P. A.; Stefan, I.; Vaquero, V.; Werner, V.; Wimmer, K.; Xu, Z. in Phys. Rev. Lett. (2017). 118(24) 242501.
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Anomalies in the Charge Yields of Fission Fragments from the ²³⁸U(n,f) Reaction. Wilson, J. N.; Lebois, M.; Qi, L.; Amador-Celdran, P.; Bleuel, D.; Briz, J. A.; Carroll, R.; Catford, W.; De Witte, H.; Doherty, D. T.; Eloirdi, R.; Georgiev, G.; Gottardo, A.; Goasduff, A.; Hadyńska-Klęk, K.; Hauschild, K.; Hess, H.; Ingeberg, V.; Konstantinopoulos, T.; Ljungvall, J.; Lopez-Martens, A.; Lorusso, G.; Lozeva, R.; Lutter, R.; Marini, P.; Matea, I.; Materna, T.; Mathieu, L.; Oberstedt, A.; Oberstedt, S.; Panebianco, S.; Podolyák, Zs.; Porta, A.; Regan, P. H.; Reiter, P.; Rezynkina, K.; Rose, S. J.; Sahin, E.; Seidlitz, M.; Serot, O.; Shearman, R.; Siebeck, B.; Siem, S.; Smith, A. G.; Tveten, G. M.; Verney, D.; Warr, N.; Zeiser, F.; Zielinska, M. in Phys. Rev. Lett. (2017). 118(22) 222501.
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E2 decay strength of the M1 scissors mode of ¹⁵⁶Gd and its first excited rotational state. Beck, T.; Beller, J.; Pietralla, N.; Bhike, M.; Birkhan, J.; Derya, V.; Gayer, U.; Hennig, A.; Isaak, J.; Löher, B.; Ponomarev, V. Yu.; Richter, A.; Romig, C.; Savran, D.; Scheck, M.; Tornow, W.; Werner, V.; Zilges, A.; Zweidinger, M. in Phys. Rev. Lett. (2017). 118(21) 212502.
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Nuclear structure investigations of ⁸⁴Sr and ⁸⁶Sr using γ-ray spectroscopic methods. Duckwitz, H.; Petkov, P.; Thomas, T.; Ahn, T.; Blazhev, A.; Cooper, N.; Fransen, C.; Hinton, M.; Ilie, G.; Jolie, J.; Werner, V. in Nuclear Physics A (2017). 965(Supplement C) 13 - 56.
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On the quadrupole collectivity in the yrast band of ¹⁶⁸Yb. Petkov, P.; Dewald, A.; Möller, O.; Deloncle, I.; Chapman, R.; Pascu, S.; Bucurescu, D.; Tonev, D.; Reese, M.; Fransen, C.; Araddad, S.Y.; Asova, G.; Copnell, J.; Goutev, N.; Hackstein, M.; Jolie, J.; Lisle, J.C.; Mo, J.N.; Pissulla, Th.; Rother, W.; Smith, A.G.; Tenereiro, C.; Thompson, D.M.; Zell, K.O. in Nuclear Physics A (2017). 957 240 - 258.
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Effective proton-neutron interaction near the drip line from unbound states in F-25,F-26. Vandebrouck, M.; Lepailleur, A.; Sorlin, O.; Aumann, T.; Caesar, C.; Holl, M.; Panin, V.; Wamers, F.; Stroberg, S. R.; Holt, J. D.; Santos, F. de Oliveira; Alvarez-Pol, H.; Atar, L.; Avdeichikov, V.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Bogner, S. K.; Boillos, J. M.; Boretzky, K.; Borge, M. J. G.; Caamano, M.; Casarejos, E.; Catford, W.; Cederkall, J.; Chartier, M.; Chulkov, L.; Cortina-Gil, D.; Cravo, E.; Crespo, R.; Pramanik, U. Datta; Diaz Fernandez, P.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Galaviz, D.; Geissel, H.; Gernhaeuser, R.; Gibelin, J.; Golubev, P.; Goebel, K.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Heinz, A.; Henriques, A.; Hergert, H.; Hufnagel, A.; Ignatov, A.; Johansson, H. T.; Jonson, B.; Kahlbow, J.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knyazev, A.; Kroll, T.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lindberg, S.; Machado, J.; Marganiec, J.; Marques, F. M.; Movsesyan, A.; Nacher, E.; Najafi, M.; Nikolskii, E.; Nilsson, T.; Nociforo, C.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Reifarth, R.; Ribeiro, G.; Rigollet, C.; Roeder, M.; Rossi, D.; Savran, D.; Scheit, H.; Schwenk, A.; Simon, H.; Syndikus, I.; Taylor, J. T.; Tengblad, O.; Thies, R.; Togano, Y.; Velho, P.; Volkov, V.; Wagner, A.; Weick, H.; Wheldon, C.; Wilson, G.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M.; Zilges, A.; Zuber, K.; Collaboration, R3B in Phys. Rev. C (2017). 96(5)
Background: Odd-odd nuclei, around doubly closed shells, have been extensively used to study proton-neutron interactions. However, the evolution of these interactions as a function of the binding energy, ultimately when nuclei become unbound, is poorly known. The F-26 nucleus, composed of a deeply bound pi 0d(5/2) proton and an unbound v0d(3/2) neutron on top of an O-24 core, is particularly adapted for this purpose. The coupling of this proton and neutron results in a J(pi) = 1(1)(+) - 4(1)(+) multiplet, whose energies must be determined to study the influence of the proximity of the continuum on the corresponding proton-neutron interaction. The J(pi) = 1(1)(+), 2(1)(+), 4(1)(+) bound states have been determined, and only a clear identification of the J(pi) = 3(1)(+) is missing. Purpose: We wish to complete the study of the J(pi) = 1(1)(+) - 4(1)(+) multiplet in F-26, by studying the energy and width of the J(pi) = 3(1)(+) unbound state. The method was first validated by the study of unbound states in F-25, for which resonances were already observed in a previous experiment. Method: Radioactive beams of Ne-26 and Ne-27, produced at about 440AMeV by the fragment separator at the GSI facility were used to populate unbound states in F-25 and F-26 via one-proton knockout reactions on a CH2 target, located at the object focal point of the (RB)-B-3/LAND setup. The detection of emitted. rays and neutrons, added to the reconstruction of the momentum vector of the A - 1 nuclei, allowed the determination of the energy of three unbound states in F-25 and two in F-26. Results: Based on its width and decay properties, the first unbound state in F-25, at the relative energy of 49(9) keV, is proposed to be a J(pi) = 1/ 2(-) arising from a p1/2 proton- hole state. In F-26, the first resonance at 323(33) keV is proposed to be the J(pi) = 3(1)(+) member of the J(pi) = 1(1)(+) - 4(1)(+) multiplet. Energies of observed states in F-25,F-26 have been compared to calculations using the independent-particle shell model, a phenomenological shell model, and the ab initio valence-space in-medium similarity renormalization group method. Conclusions: The deduced effective proton- neutron interaction is weakened by about 30-40% in comparison to the models, pointing to the need for implementing the role of the continuum in theoretical descriptions or to a wrong determination of the atomic mass of F-26.
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Lifetime measurements with improved precision in S-30,S-32 and possible influence of large-scale clustering on the appearance of strongly deformed states. Petkov, P.; Mueller-Gatermann, C.; Dewald, A.; Blazhev, A.; Fransen, C.; Jolie, J.; Scholz, P.; Zell, K. O.; Zilges, A. in Phys. Rev. C (2017). 96(3)
The formation of large size clusters and/or their relative motion as possible excitation mode are suggested to be closely related to the origin of deformation in specific cases. In S-32, the consideration of some excitations in this nucleus as based on the existence of two doubly magic O-16 clusters offers a possible solution to the long-standing problem of missing quadrupole collectivity in shell-model calculations aiming to describe electromagnetic E-2 transition strengths and quadrupole moments. To experimentally check again this collectivity, lifetime measurements were performed on S-30 and S-32. In S-32, at least, the reproduction of a number of observables supports the cluster scenario. Additionally, the superdeformed yrast band in Zr-80 could find an explanation as based on the relative motion of two Ca-40 clusters. Simultaneously, a necessity arises to revise experimentally some lifetimes derived in the past within the Blaugrund approximation when using the Doppler-shift attenuation method.
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A dedicated {AMS} setup for medium mass isotopes at the Cologne {FN} tandem accelerator. Schiffer, M.; Altenkirch, R.; Feuerstein, C.; Müller-Gatermann, C.; Hackenberg, G.; Herb, S.; Bhandari, P.; Heinze, S.; Stolz, A.; Dewald, A. in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (2017). 406 287--291.
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Lifetime measurements in 100Ru. Konstantinopoulos, T.; Petkov, P.; Goasduff, A.; Arici, T.; Astier, A.; Atanasova, L.; Axiotis, M.; Bonatsos, D.; Detistov, P.; Dewald, A.; Eller, M. J.; Foteinou, V.; Gargano, A.; Georgiev, G.; Gladnishki, K.; Gottardo, A.; Harissopulos, S.; Hess, H.; Kaim, S.; Kocheva, D.; Kusoglu, A.; Lagoyannis, A.; Ljungvall, J.; Lutter, R.; Matea, I.; Melon, B.; Mertzimekis, T. J.; Nannini, A.; Petrache, C. M.; Petrovici, A.; Provatas, G.; Reiter, P.; Rocchini, M.; Roccia, S.; Seidlitz, M.; Siebeck, B.; Suzuki, D.; Warr, N.; De Witte, H.; Zerrouki, T. in Phys. Rev. C (2017). 95(1) 014309.
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Evolution of collectivity in the N=100 isotones near ¹⁷⁰Yb. Karayonchev, V.; Régis, J.-M.; Jolie, J.; Blazhev, A.; Altenkirch, R.; Ansari, S.; Dannhoff, M.; Diel, F.; Esmaylzadeh, A.; Fransen, C.; Gerst, R.-B.; Moschner, K.; Müller-Gatermann, C.; Saed-Samii, N.; Stegemann, S.; Warr, N.; Zell, K. O. in Phys. Rev. C (2017). 95(3) 034316.
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Compton imaging with a highly-segmented, position-sensitive HPGe detector. Steinbach, T.; Hirsch, R.; Reiter, P.; Birkenbach, B.; Bruyneel, B.; Eberth, J.; Gernhäuser, R.; Hess, H.; Lewandowski, L.; Maier, L.; Schlarb, M.; Weiler, B.; Winkel, M. in The European Physical Journal A (2017). 53(2) 23.
A Compton camera based on a highly-segmented high-purity germanium (HPGe) detector and a double-sided silicon-strip detector (DSSD) was developed, tested, and put into operation; the origin of {\\($}{\backslash}gamma{\$\)} \($\gamma$\) radiation was determined successfully. The Compton camera is operated in two different modes. Coincidences from Compton-scattered {\\($}{\backslash}gamma{\$\)} \($\gamma$\) -ray events between DSSD and HPGe detector allow for best angular resolution; while the high-efficiency mode takes advantage of the position sensitivity of the highly-segmented HPGe detector. In this mode the setup is sensitive to the whole {\\($} 4{\backslash}pi{\$\)} 4 \($\pi$\) solid angle. The interaction-point positions in the 36-fold segmented large-volume HPGe detector are determined by pulse-shape analysis (PSA) of all HPGe detector signals. Imaging algorithms were developed for each mode and successfully implemented. The angular resolution sensitively depends on parameters such as geometry, selected multiplicity and interaction-point distances. Best results were obtained taking into account the crosstalk properties, the time alignment of the signals and the distance metric for the PSA for both operation modes. An angular resolution between {\\($} 13.8^{\{}{\backslash}circ{\}}{\$\)} 13 . 8 ∘ and {\\($} 19.1^{\{}{\backslash}circ{\}}{\$\)} 19 . 1 ∘ , depending on the minimal interaction-point distance for the high-efficiency mode at an energy of 1275 keV, was achieved. In the coincidence mode, an increased angular resolution of {\\($} 4.6^{\{}{\backslash}circ{\}}{\$\)} 4 . 6 ∘ was determined for the same {\\($}{\backslash}gamma{\$\)} \($\gamma$\) -ray energy.
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Conceptual design of the AGATA 1π array at GANIL. Clément, E.; Michelagnoli, C.; de France, G.; Li, H.J.; Lemasson, A.; Dejean, C. Barthe; Beuzard, M.; Bougault, P.; Cacitti, J.; Foucher, J.-L.; Fremont, G.; Gangnant, P.; Goupil, J.; Houarner, C.; Jean, M.; Lefevre, A.; Legeard, L.; Legruel, F.; Maugeais, C.; Ménager, L.; Ménard, N.; Munoz, H.; Ozille, M.; Raine, B.; Ropert, J.A.; Saillant, F.; Spitaels, C.; Tripon, M.; Vallerand, Ph.; Voltolini, G.; Korten, W.; Salsac, M.-D.; Theisen, Ch.; Zielińska, M.; Joannem, T.; Karolak, M.; Kebbiri, M.; Lotode, A.; Touzery, R.; Walter, Ch.; Korichi, A.; Ljungvall, J.; Lopez-Martens, A.; Ralet, D.; Dosme, N.; Grave, X.; Karkour, N.; Lafay, X.; Legay, E.; Kojouharov, I.; Domingo-Pardo, C.; Gadea, A.; Pérez-Vidal, R.M.; Civera, J.V.; Birkenbach, B.; Eberth, J.; Hess, H.; Lewandowski, L.; Reiter, P.; Nannini, A.; Angelis, G. De; Jaworski, G.; John, P.; Napoli, D.R.; Valiente-Dobón, J.J.; Barrientos, D.; Bortolato, D.; Benzoni, G.; Bracco, A.; Brambilla, S.; Camera, F.; Crespi, F.C.L.; Leoni, S.; Million, B.; Pullia, A.; Wieland, O.; Bazzacco, D.; Lenzi, S.M.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Recchia, F.; Bellato, M.; Isocrate, R.; Canet, F.J. Egea; Didierjean, F.; Duchêne, G.; Baumann, R.; Brucker, M.; Dangelser, E.; Filliger, M.; Friedmann, H.; Gaudiot, G.; Grapton, J.-N.; Kocher, H.; Mathieu, C.; Sigward, M.-H.; Thomas, D.; Veeramootoo, S.; Dudouet, J.; Stézowski, O.; Aufranc, C.; Aubert, Y.; Labiche, M.; Simpson, J.; Burrows, I.; Coleman-Smith, P.J.; Grant, A.; Lazarus, I.H.; Morrall, P.S.; Pucknell, V.F.E.; Boston, A.; Judson, D.S.; Lalović, N.; Nyberg, J.; Collado, J.; González, V.; Kuti, I.; Nyakó, B.M.; Maj, A.; Rudigier, M. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2017). 855(Supplement C) 1 - 12.
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Nuclear-structure studies of exotic nuclei with MINIBALL. Butler, P A; Cederkall, J; Reiter, P in Journal of Physics G: Nuclear and Particle Physics (2017). 44(4) 044012.
High-resolution γ -ray spectroscopy has been established at ISOLDE for nuclear-structure and nuclear-reaction studies with reaccelerated radioactive ion beams provided by the REX-ISOLDE facility. The MINIBALL spectrometer comprises 24 six-fold segmented, encapsulated high-purity germanium crystals. It was specially designed for highest γ -ray detection efficiency which is advantageous for low-intensity radioactive ion beams. The MINIBALL array has been used in numerous Coulomb-excitation and transfer-reaction experiments with exotic ion beams of energies up to 3 MeV A –1 . The physics case covers a wide range of topics which are addressed with beams ranging from neutron-rich magnesium isotopes up to heavy radium isotopes. In the future the HIE-ISOLDE will allow the in-beam γ -ray spectroscopy program to proceed with higher secondary-beam intensity, higher beam energy and better beam quality.
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Measurement of lifetimes in ⁶²’⁶⁴Fe,⁶¹’⁶³Co, and ⁵⁹Mn. Klintefjord, M; Ljungvall, J; Görgen, A; Lenzi, S M; Bello Garrote, F L; Blazhev, A; Clément, E; de France, G; Delaroche, J P; Désesquelles, P; Dewald, A; Doherty, D T; Fransen, C; Gengelbach, A; Georgiev, G; Girod, M; Goasduff, A; Gottardo, A; Hadyńska-Klȩk, K; Jacquot, B; Konstantinopoulos, T; Korichi, A; Lemasson, A; Libert, J; Lopez-Martens, A; Michelagnoli, C; Navin, A; Nyberg, J; Pérez-Vidal, R M; Roccia, S; Sahin, E; Stefan, I; Stuchbery, A E; Zielińska, M; Barrientos, D; Birkenbach, B; Boston, A; Charles, L; Ciemala, M; Dudouet, J; Eberth, J; Gadea, A; González, V; Harkness-Brennan, L; Hess, H; Jungclaus, A; Korten, W; Menegazzo, R; Mengoni, D; Million, B; Pullia, A; Ralet, D; Recchia, F; Reiter, P; Salsac, M D; Sanchis, E; Stezowski, O; Theisen, Ch; Valiente Dobon, J J in Phys. Rev. C (2017). 95(2) 024312. 11 p.
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Identification of the crossing point at N=21 between normal and intruder configurations. Lica, R.; Rotaru, F.; Borge, M. J. G.; Grévy, S.; Negoiifmmode \mbox{\c{t}}else \c{t}\fi{}ifmmode \u{a}else \u{a}\fi{}, F.; Poves, A.; Sorlin, O.; Andreyev, A. N.; Borcea, R.; Costache, C.; De Witte, H.; Fraile, L. M.; Greenlees, P. T.; Huyse, M.; Ionescu, A.; Kisyov, S.; Konki, J.; Lazarus, I.; Madurga, M.; Mifmmode \u{a}else \u{a}\fi{}rginean, N.; Mifmmode \u{a}else \u{a}\fi{}rginean, R.; Mihai, C.; Mihai, R. E.; Negret, A.; Page, R. D.; Pakarinen, J.; Pascu, S.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; ifmmode \mbox{\c{S}}else \c{S}\fi{}erban, A.; Sotty, C. O.; Stan, L.; Stifmmode \u{a}else \u{a}\fi{}noiu, M.; Tengblad, O.; Turturicifmmode \u{a}else \u{a}\fi{}, A.; Van Duppen, P.; Wadsworth, R.; Warr, N. in Phys. Rev. C (2017). 95(2) 021301.
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Characterization and calibration of radiation-damaged double-sided silicon strip detectors. Kaya, L.; Vogt, A.; Reiter, P.; Birkenbach, B.; Hirsch, R.; Arnswald, K.; Hess, H.; Seidlitz, M.; Steinbach, T.; Warr, N.; Wolf, K.; Stahl, C.; Pietralla, N.; Limböck, T.; Meerholz, K.; Lutter, R. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2017). 855 109 - 117.
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⁹⁶Kr - Low-Z Boundary of the Island of Deformation at N = 60. Dudouet, J.; Lemasson, A.; Duchêne, G.; Rejmund, M.; Clément, E.; Michelagnoli, C.; Didierjean, F.; Korichi, A.; Maquart, G.; Stezowski, O.; Lizarazo, C.; Pérez-Vidal, R. M.; Andreoiu, C.; de Angelis, G.; Astier, A.; Delafosse, C.; Deloncle, I.; Dombradi, Z.; de France, G.; Gadea, A.; Gottardo, A.; Jacquot, B.; Jones, P.; Konstantinopoulos, T.; Kuti, I.; Le Blanc, F.; Lenzi, S. M.; Li, G.; Lozeva, R.; Million, B.; Napoli, D. R.; Navin, A.; Petrache, C. M.; Pietralla, N.; Ralet, D.; Ramdhane, M.; Redon, N.; Schmitt, C.; Sohler, D.; Verney, D.; Barrientos, D.; Birkenbach, B.; Burrows, I.; Charles, L.; Collado, J.; Cullen, D. M.; Désesquelles, P.; Domingo Pardo, C.; González, V.; Harkness-Brennan, L.; Hess, H.; Judson, D. S.; Karolak, M.; Korten, W.; Labiche, M.; Ljungvall, J.; Menegazzo, R.; Mengoni, D.; Pullia, A.; Recchia, F.; Reiter, P.; Salsac, M. D.; Sanchis, E.; Theisen, Ch.; Valiente-Dobón, J. J.; Zielińska, M. in Phys. Rev. Lett. (2017). 118(16) 162501.
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Collectivity in196,198Pb isotopes probed in Coulomb-excitation experiments at {REX}-{ISOLDE}. Pakarinen, J; Grahn, T; Gaffney, L P; Algora, A; Bauer, C; Blazhev, A; Bree, N; Cocolios, T E; Witte, H De; Diriken, J; Fernier, P; Hady{{{'n}}}ska-Klȩk, K; Herz{{á}}{\v{n}}, A; Huyse, M; Iwanicki, J; Jakobsson, U; Jenkins, D; Kesteloot, N; Konki, J; Lannoo, B; Papadakis, P; Peura, P; Rahkila, P; Rainovski, G; Rapisarda, E; Reiter, P; Sambi, S; Scheck, M; Seibeck, B; Seidlitz, M; Stora, T; Duppen, P Van; Warr, N; Wenander, F; Vermeulen, M J; Voulot, D; Wrzosek-Lipska, K; Zieli{{{'n}}}ska, M in Journal of Physics G: Nuclear and Particle Physics (2017). 44(6) 064009.
The neutron-deficient Pb isotopes have been studied in Coulomb-excitation experiments employing the Miniball γ-ray spectrometer and radioactive ion beams from the REX-ISOLDE post-accelerator at CERN. The reduced transition probabilities of the first excited 2+ states in 196Pb and 198Pb nuclei have been measured for the first time. Values of W.u. and W.u., were obtained, respectively. The experiment sheds light on the development of collectivity when moving from the regime governed by the generalised seniority scheme to a region, where intruding structures, associated with different deformed shapes, start to come down in energy and approach the spherical ground state.
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Beta decay studies of n-rich Cs isotopes with the {ISOLDE} Decay Station. Lic{\u{a}}, R; Benzoni, G; Morales, A I; Borge, M J G; Fraile, L M; Mach, H; Madurga, M; Sotty, C; Vedia, V; Witte, H De; Benito, J; Berry, T; Blasi, N; Bracco, A; Camera, F; Ceruti, S; Charviakova, V; Cieplicka-Ory{{{'n}}}czak, N; Costache, C; Crespi, F C L; Creswell, J; Fern{{á}}ndez-Mart{\'{i}}nez, G; Fynbo, H; Greenlees, P; Homm, I; Huyse, M; Jolie, J; Karayonchev, V; Köster, U; Konki, J; Kröll, T; Kurcewicz, J; Kurtukian-Nieto, T; Lazarus, I; Leoni, S; Lund, M; Marginean, N; Marginean, R; Mihai, C; Mihai, R; Negret, A; Orduz, A; Patyk, Z; Pascu, S; Pucknell, V; Rahkila, P; Regis, J M; Rotaru, F; Saed-Sami, N; S{{á}}nchez-Tembleque, V; Stanoiu, M; Tengblad, O; Thuerauf, M; Turturica, A; Duppen, P Van; Warr, N in Journal of Physics G: Nuclear and Particle Physics (2017). 44(5) 054002.
Neutron-rich Ba isotopes are expected to exhibit octupolar correlations, reaching their maximum in isotopes around mass A = 146. The odd-A neutron-rich members of this isotopic chain show typical patterns related to non-axially symmetric shapes, which are however less marked compared to even-A ones, pointing to a major contribution from vibrations. In the present paper we present results from a recent study focused on 148–150Cs β-decay performed at the ISOLDE Decay Station equipped with fast-timing detectors. A detailed analysis of the measured decay half-lives and decay scheme of 149Ba is presented, giving a first insight in the structure of this neutron-rich nucleus.
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Lifetime measurements in ¹⁰⁰Ru. Konstantinopoulos, T.; Petkov, P.; Goasduff, A.; Arici, T.; Astier, A.; Atanasova, L.; Axiotis, M.; Bonatsos, D.; Detistov, P.; Dewald, A.; Eller, M. J.; Foteinou, V.; Gargano, A.; Georgiev, G.; Gladnishki, K.; Gottardo, A.; Harissopulos, S.; Hess, H.; Kaim, S.; Kocheva, D.; Kusoglu, A.; Lagoyannis, A.; Ljungvall, J.; Lutter, R.; Matea, I.; Melon, B.; Mertzimekis, T. J.; Nannini, A.; Petrache, C. M.; Petrovici, A.; Provatas, G.; Reiter, P.; Rocchini, M.; Roccia, S.; Seidlitz, M.; Siebeck, B.; Suzuki, D.; Warr, N.; De Witte, H.; Zerrouki, T. in Phys. Rev. C (2017). 95(1) 014309.
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Enhanced collectivity along the N=Z line: Lifetime measurements in ⁴⁴Ti, ⁴⁸Cr, and ⁵²Fe. Arnswald, K.; Braunroth, T.; Seidlitz, M.; Coraggio, L.; Reiter, P.; Birkenbach, B.; Blazhev, A.; Dewald, A.; Fransen, C.; Fu, B.; Gargano, A.; Hess, H.; Hirsch, R.; Itaco, N.; Lenzi, S.M.; Lewandowski, L.; Litzinger, J.; Müller-Gatermann, C.; Queiser, M.; Rosiak, D.; Schneiders, D.; Siebeck, B.; Steinbach, T.; Vogt, A.; Wolf, K.; Zell, K.O. in Phys. Lett. B (2017). 772 599 - 606.
Abstract Lifetimes of the 21+ states in 44Ti, 48,50Cr, and 52Fe were determined with high accuracy exploiting the recoil distance Doppler-shift method. The reduced E2 transition strengths of 44Ti and 52Fe differ considerably from previously known values. A systematic increase in collectivity is found for the N=Z nuclei compared to neighboring isotopes. The B(E2) values along the Ti, Cr, and Fe isotopic chains are compared to shell-model calculations employing established interactions for the 0f1p shell, as well as a novel effective shell-model Hamiltonian starting from a realistic nucleon–nucleon potential. The theoretical approaches underestimate the B(E2) values for the lower-mass Ti isotopes. Strong indication is found for particle-hole cross-shell configurations, recently corroborated by similar results for the neighboring isotone 42Ca.
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Isomers and high-spin structures in the isotones ¹³⁵Xe and ¹³⁷ Ba. Vogt, A.; Birkenbach, B.; Reiter, P.; Blazhev, A.; Siciliano, M.; Hadyńska-Klęk, K.; Valiente-Dobón, J. J.; Wheldon, C.; Teruya, E.; Yoshinaga, N.; Arnswald, K.; Bazzacco, D.; Bowry, M.; Bracco, A.; Bruyneel, B.; Chakrawarthy, R. S.; Chapman, R.; Cline, D.; Corradi, L.; Crespi, F. C. L; Cromaz, M.; de Angelis, G.; Eberth, J.; Fallon, P.; Farnea, E.; Fioretto, E.; Freeman, S. J.; Fu, B.; Gadea, A.; Geibel, K.; Gelletly, W.; Gengelbach, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hayes, A. B.; Hess, H.; Hirsch, R.; Hua, H.; John, P. R.; Jolie, J.; Jungclaus, A.; Kaya, L.; Korten, W.; Lee, I. Y.; Leoni, S.; Lewandowski, L.; Liang, X.; Lunardi, S.; Macchiavelli, A. O.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Müller-Gatermann, C.; Napoli, D.; Pearson, C. J.; Pellegri, L.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Queiser, M.; Radeck, F.; Recchia, F.; Regan, P. H.; Rosiak, D.; Saed-Samii, N.; Şahin, E.; Scarlassara, F.; Schneiders, D.; Seidlitz, M.; Siebeck, B.; Sletten, G.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szilner, S.; Szpak, B.; Teng, R.; Ur, C.; Vandone, V.; Warner, D. D.; Wiens, A.; Wu, C. Y.; Zell, K. O. in Phys. Rev. C (2017). 95(2) 024316.
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EXILL—a high-efficiency, high-resolution setup for γ-spectroscopy at an intense cold neutron beam facility. Jentschel, M.; Blanc, A.; de France, G.; Köster, U.; Leoni, S.; Mutti, P.; Simpson, G.; Soldner, T.; Ur, C.; Urban, W.; Ahmed, S.; Astier, A.; Augey, L.; Back, T.; Ba̧czyk, P.; Bajoga, A.; Balabanski, D.; Belgya, T.; Benzoni, G.; Bernards, C.; Biswas, D.C.; Bocchi, G.; Bottoni, S.; Britton, R.; Bruyneel, B.; Burnett, J.; Cakirli, R.B.; Carroll, R.; Catford, W.; Cederwall, B.; Celikovic, I.; Cieplicka-Oryńczak, N.; Clement, E.; Cooper, N.; Crespi, F.; Csatlos, M.; Curien, D.; Czerwiński, M.; Danu, L.S.; Davies, A.; Didierjean, F.; Drouet, F.; Duchêne, G.; Ducoin, C.; Eberhardt, K.; Erturk, S.; Fraile, L.M.; Gottardo, A.; Grente, L.; Grocutt, L.; Guerrero, C.; Guinet, D.; Hartig, A.-L.; Henrich, C.; Ignatov, A.; Ilieva, S.; Ivanova, D.; John, B.V.; John, R.; Jolie, J.; Kisyov, S.; Krticka, M.; Konstantinopoulos, T.; Korgul, A.; Krasznahorkay, A.; Kröll, T.; Kurpeta, J.; Kuti, I.; Lalkovski, S.; Larijani, C.; Leguillon, R.; Lica, R.; Litaize, O.; Lozeva, R.; Magron, C.; Mancuso, C.; Martinez, E. Ruiz; Massarczyk, R.; Mazzocchi, C.; Melon, B.; Mengoni, D.; Michelagnoli, C.; Million, B.; Mokry, C.; Mukhopadhyay, S.; Mulholland, K.; Nannini, A.; Napoli, D.R.; Olaizola, B.; Orlandi, R.; Patel, Z.; Paziy, V.; Petrache, C.; Pfeiffer, M.; Pietralla, N.; Podolyak, Z.; Ramdhane, M.; Redon, N.; Regan, P.; Regis, J.M.; Regnier, D.; Oliver, R. J.; Rudigier, M.; Runke, J.; Rza̧ca-Urban, T.; Saed-Samii, N.; Salsac, M.D.; Scheck, M.; Schwengner, R.; Sengele, L.; Singh, P.; Smith, J.; Stezowski, O.; Szpak, B.; Thomas, T.; Thürauf, M.; Timar, J.; Tom, A.; Tomandl, I.; Tornyi, T.; Townsley, C.; Tuerler, A.; Valenta, S.; Vancraeyenest, A.; Vandone, V.; Vanhoy, J.; Vedia, V.; Warr, N.; Werner, V.; Wilmsen, D.; Wilson, E.; Zerrouki, T.; Zielinska, M. in Journal of Instrumentation (2017). 12(11) P11003.
In the EXILL campaign a highly efficient array of high purity germanium (HPGe) detectors was operated at the cold neutron beam facility PF1B of the Institut Laue-Langevin (ILL) to carry out nuclear structure studies, via measurements of γ-rays following neutron-induced capture and fission reactions. The setup consisted of a collimation system producing a pencil beam with a thermal capture equivalent flux of about 10 8 n s −1 cm −2 at the target position and negligible neutron halo. The target was surrounded by an array of eight to ten anti-Compton shielded EXOGAM Clover detectors, four to six anti-Compton shielded large coaxial GASP detectors and two standard Clover detectors. For a part of the campaign the array was combined with 16 LaBr 3 :(Ce) detectors from the FATIMA collaboration. The detectors were arranged in an array of rhombicuboctahedron geometry, providing the possibility to carry out very precise angular correlation and directional-polarization correlation measurements. The triggerless acquisition system allowed a signal collection rate of up to 6 × 10 5 Hz. The data allowed to set multi-fold coincidences to obtain decay schemes and in combination with the FATIMA array of LaBr 3 :(Ce) detectors to analyze half-lives of excited levels in the pico- to microsecond range. Precise energy and efficiency calibrations of EXILL were performed using standard calibration sources of 133 Ba, 60 Co and 152 Eu as well as data from the reactions 27 Al(n,γ) 28 Al and 35 Cl( n ,γ) 36 Cl in the energy range from 30 keV up to 10 MeV.
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Lifetime measurement of neutron-rich even-even molybdenum isotopes. Ralet, D.; Pietri, S.; Rodr\'{i}guez, T.; Alaqeel, M.; Alexander, T.; Alkhomashi, N.; Ameil, F.; Arici, T.; Ataifmmode \mbox{\c{c}}else \c{c}\fi{}, A.; Avigo, R.; Bäck, T.; Bazzacco, D.; Birkenbach, B.; Boutachkov, P.; Bruyneel, B.; Bruce, A. M.; Camera, F.; Cederwall, B.; Ceruti, S.; Clément, E.; Cortés, M. L.; Curien, D.; De Angelis, G.; Désesquelles, P.; Dewald, M.; Didierjean, F.; Domingo-Pardo, C.; Doncel, M.; Duchêne, G.; Eberth, J.; Gadea, A.; Gerl, J.; Ghazi Moradi, F.; Geissel, H.; Goigoux, T.; Goel, N.; Golubev, P.; González, V.; Górska, M.; Gottardo, A.; Gregor, E.; Guastalla, G.; Givechev, A.; Habermann, T.; Hackstein, M.; Harkness-Brennan, L.; Henning, G.; Hess, H.; Hüyük, T.; Jolie, J.; Judson, D. S.; Jungclaus, A.; Knoebel, R.; Kojouharov, I.; Korichi, A.; Korten, W.; Kurz, N.; Labiche, M.; Lalovic, N.; Louchart-Henning, C.; Mengoni, D.; Merchán, E.; Million, B.; Morales, A. I.; Napoli, D.; Naqvi, F.; Nyberg, J.; Pietralla, N.; Podolyák, Zs.; Pullia, A.; Prochazka, A.; Quintana, B.; Rainovski, G.; Reese, M.; Recchia, F.; Reiter, P.; Rudolph, D.; Salsac, M. D.; Sanchis, E.; Sarmiento, L. G.; Schaffner, H.; Scheidenberger, C.; Sengele, L.; Singh, B. S. Nara; Singh, P. P.; Stahl, C.; Stezowski, O.; Thoele, P.; Valiente Dobon, J. J.; Weick, H.; Wendt, A.; Wieland, O.; Winfield, J. S.; Wollersheim, H. J.; Zielinska, M. in Phys. Rev. C (2017). 95(3) 034320.
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Low-lying structure and shape evolution in neutron-rich Se isotopes. Chen, S.; Doornenbal, P.; Obertelli, A.; Rodríguez, T. R.; Authelet, G.; Baba, H.; Calvet, D.; Château, F.; Corsi, A.; Delbart, A.; Gheller, J.-M.; Giganon, A.; Gillibert, A.; Lapoux, V.; Motobayashi, T.; Niikura, M.; Paul, N.; Roussé, J.-Y.; Sakurai, H.; Santamaria, C.; Steppenbeck, D.; Taniuchi, R.; Uesaka, T.; Ando, T.; Arici, T.; Blazhev, A.; Browne, F.; Bruce, A. M.; Caroll, R.; Chung, L. X.; Cortés, M. L.; Dewald, M.; Ding, B.; Flavigny, F.; Franchoo, S.; Górska, M.; Gottardo, A.; Jungclaus, A.; Lee, J.; Lettmann, M.; Linh, B. D.; Liu, J.; Liu, Z.; Lizarazo, C.; Momiyama, S.; Moschner, K.; Nagamine, S.; Nakatsuka, N.; Nita, C. R.; Nobs, C.; Olivier, L.; Orlandi, R.; Patel, Z.; Podolyak, Zs.; Rudigier, M.; Saito, T.; Shand, C.; Söderström, P.-A.; Stefan, I.; Vaquero, V.; Werner, V.; Wimmer, K.; Xu, Z. in Phys. Rev. C (2017). 95(4) 041302.
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Experimental study of the lifetime and phase transition in neutron-rich 98,100,102Zr. Ansari, S.; Régis, J.-M.; Jolie, J.; Saed-Samii, N.; Warr, N.; Korten, W.; Zielińska, M.; Salsac, M.-D.; Blanc, A.; Jentschel, M.; Köster, U.; Mutti, P.; Soldner, T.; Simpson, G. S.; Drouet, F.; Vancraeyenest, A.; de France, G.; Clément, E.; Stezowski, O.; Ur, C. A.; Urban, W.; Regan, P. H.; Podolyák, Zs.; Larijani, C.; Townsley, C.; Carroll, R.; Wilson, E.; Mach, H.; Fraile, L. M.; Paziy, V.; Olaizola, B.; Vedia, V.; Bruce, A. M.; Roberts, O. J.; Smith, J. F.; Scheck, M.; Kröll, T.; Hartig, A.-L.; Ignatov, A.; Ilieva, S.; Lalkovski, S.; Mărginean, N.; Otsuka, T.; Shimizu, N.; Togashi, T.; Tsunoda, Y. in Phys. Rev. C (2017). 96(5) 054323.
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Are There Signatures of Harmonic Oscillator Shells Far from Stability? First Spectroscopy of 110Zr. Paul, N.; Corsi, A.; Obertelli, A.; Doornenbal, P.; Authelet, G.; Baba, H.; Bally, B.; Bender, M.; Calvet, D.; Château, F.; Chen, S.; Delaroche, J.-P.; Delbart, A.; Gheller, J.-M.; Giganon, A.; Gillibert, A.; Girod, M.; Heenen, P.-H.; Lapoux, V.; Libert, J.; Motobayashi, T.; Niikura, M.; Otsuka, T.; Rodríguez, T. R.; Roussé, J.-Y.; Sakurai, H.; Santamaria, C.; Shimizu, N.; Steppenbeck, D.; Taniuchi, R.; Togashi, T.; Tsunoda, Y.; Uesaka, T.; Ando, T.; Arici, T.; Blazhev, A.; Browne, F.; Bruce, A. M.; Carroll, R.; Chung, L. X.; Cortés, M. L.; Dewald, M.; Ding, B.; Flavigny, F.; Franchoo, S.; Górska, M.; Gottardo, A.; Jungclaus, A.; Lee, J.; Lettmann, M.; Linh, B. D.; Liu, J.; Liu, Z.; Lizarazo, C.; Momiyama, S.; Moschner, K.; Nagamine, S.; Nakatsuka, N.; Nita, C.; Nobs, C. R.; Olivier, L.; Patel, Z.; Podolyák, Zs.; Rudigier, M.; Saito, T.; Shand, C.; Söderström, P.-A.; Stefan, I.; Orlandi, R.; Vaquero, V.; Werner, V.; Wimmer, K.; Xu, Z. in Phys. Rev. Lett. (2017). 118(3) 032501.
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Low collectivity of the 2+1 state of 212Po. Kocheva, D.; Rainovski, G.; Jolie, J.; Pietralla, N.; Blazhev, A.; Altenkirch, R.; Ansari, S.; Astier, A.; Bast, M.; Beckers, M.; Braunroth, Th.; Cappellazzo, M.; Dewald, A.; Diel, F.; Djongolov, M.; Fransen, C.; Gladnishki, K.; Goldkuhle, A.; Hennig, A.; Karayonchev, V.; Keatings, J. M.; Kluge, E.; Kröll, Th.; Litzinger, J.; Moschner, K.; Müller-Gatermann, C.; Petkov, P.; Scheck, M.; Scholz, Ph.; Schmidt, T.; Spagnoletti, P.; Stahl, C.; Stegmann, R.; Stolz, A.; Vogt, A.; Warr, N.; Werner, V.; Wölk, D.; Zamora, J. C.; Zell, K. O.; Ponomarev, V. Yu.; Van Isacker, P. in Phys. Rev. C (2017). 96(4) 044305.
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Lifetime measurements with improved precision in 30,32S and possible influence of large-scale clustering on the appearance of strongly deformed states. Petkov, P.; Müller-Gatermann, C.; Dewald, A.; Blazhev, A.; Fransen, C.; Jolie, J.; Scholz, P.; Zell, K. O.; Zilges, A. in Phys. Rev. C (2017). 96(3) 034326.
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Cross-shell excitations from the fp shell: Lifetime measurements in 61Zn. Queiser, M.; Vogt, A.; Seidlitz, M.; Reiter, P.; Togashi, T.; Shimizu, N.; Utsuno, Y.; Otsuka, T.; Honma, M.; Petkov, P.; Arnswald, K.; Altenkirch, R.; Birkenbach, B.; Blazhev, A.; Braunroth, T.; Dewald, A.; Eberth, J.; Fransen, C.; Fu, B.; Hess, H.; Hetzenegger, R.; Hirsch, R.; Jolie, J.; Karayonchev, V.; Kaya, L.; Lewandowski, L.; Müller-Gatermann, C.; Régis, J.-M.; Rosiak, D.; Schneiders, D.; Siebeck, B.; Steinbach, T.; Wolf, K.; Zell, K.-O. in Phys. Rev. C (2017). 96(4) 044313.
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Determination of the neutron-capture rate of C-17 for r-process nucleosynthesis. Heine, M.; Typel, S.; Wu, M. R.; Adachi, T.; Aksyutina, Y.; Alcantara, J.; Altstadt, S.; Alvarez-Pol, H.; Ashwood, N.; Atar, L.; Aumann, T.; Avdeichikov, V.; Barr, M.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Burgunder, G.; Caamano, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkaell, J.; Chakraborty, S.; Chartier, M.; Chulkov, L. V.; Cortina-Gil, D.; Crespo, R.; Pramanik, U. Datta; Fernandez, P. Diaz; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Freudenberger, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhaeuser, R.; Goebel, K.; Golubev, P.; Diaz, D. Gonzalez; Hagdahl, J.; Heftrich, T.; Heil, M.; Heinz, A.; Henriques, A.; Holl, M.; Ickert, G.; Ignatov, A.; Jakobsson, B.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knoebel, R.; Kroell, T.; Kruecken, R.; Kurcewicz, J.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lepyoshkina, O.; Lindberg, S.; Machado, J.; Marganiec, J.; Martinez-Pinedo, G.; Maroussov, V.; Mostazo, M.; Movsesyan, A.; Najafi, A.; Neff, T.; Nilsson, T.; Nociforo, C.; Panin, V.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Prochazka, A.; Rahaman, A.; Rastrepina, G.; Reifarth, R.; Ribeiro, G.; Ricciardi, M. V.; Rigollet, C.; Riisager, K.; Roeder, M.; Rossi, D.; del Rio, J. Sanchez; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Stoica, V.; Streicher, B.; Taylor, J. T.; Tengblad, O.; Terashima, S.; Thies, R.; Togano, Y.; Uberseder, E.; Van de Walle, J.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Weigand, M.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M. V.; Zilges, A.; Zuber, K.; Collaboration, R3B in Phys. Rev. C (2017). 95(1)
With the (RB)-B-3-LAND setup at GSI we have measured exclusive relative-energy spectra of the Coulomb dissociation of C-18 at a projectile energy around 425A MeV on a lead target, which are needed to determine the radiative neutron-capture cross sections of C-17 into the ground state of C-18. Those data have been used to constrain theoretical calculations for transitions populating excited states in C-18. This allowed to derive the astrophysical cross section sigma(n gamma){*}. accounting for the thermal population of C-17 target states in astrophysical scenarios. The experimentally verified capture rate is significantly lower than those of previously obtained Hauser-Feshbach estimations at temperatures T-9 <= 1 GK. Network simulations with updated neutron-capture rates and hydrodynamics according to the neutrino-driven wind model as well as the neutron-star merger scenario reveal no pronounced influence of neutron capture of C-17 on the production of second-and third-peak elements in contrast to earlier sensitivity studies.
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Pulse shape analysis and position determination in segmented HPGe detectors: The AGATA detector library. Bruyneel, B.; Birkenbach, B.; Reiter, P. in The European Physical Journal A (2016). 52(3) 70.
The AGATA Detector Library (ADL) was developed for the calculation of signals from highly segmented large volume high-purity germanium (HPGe) detectors. ADL basis sets comprise a huge amount of calculated position-dependent detector pulse shapes. A basis set is needed for Pulse Shape Analysis (PSA). By means of PSA the interaction position of a {\\($} {\backslash}gamma{\$\)} -ray inside the active detector volume is determined. Theoretical concepts of the calculations are introduced and cover the relevant aspects of signal formation in HPGe. The approximations and the realization of the computer code with its input parameters are explained in detail. ADL is a versatile and modular computer code; new detectors can be implemented in this library. Measured position resolutions of the AGATA detectors based on ADL are discussed.
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Superdeformed and Triaxial States in 42Ca. Hadyńska-Klȩk, K.; Napiorkowski, P. J.; Zielińska, M.; Srebrny, J.; Maj, A.; Azaiez, F.; Valiente Dobón, J. J.; Kicińska-Habior, M.; Nowacki, F.; Naïdja, H.; Bounthong, B.; Rodríguez, T. R.; de Angelis, G.; Abraham, T.; Anil Kumar, G.; Bazzacco, D.; Bellato, M.; Bortolato, D.; Bednarczyk, P.; Benzoni, G.; Berti, L.; Birkenbach, B.; Bruyneel, B.; Brambilla, S.; Camera, F.; Chavas, J.; Cederwall, B.; Charles, L.; Ciemała, M.; Cocconi, P.; Coleman-Smith, P.; Colombo, A.; Corsi, A.; Crespi, F. C. L.; Cullen, D. M.; Czermak, A.; Désesquelles, P.; Doherty, D. T.; Dulny, B.; Eberth, J.; Farnea, E.; Fornal, B.; Franchoo, S.; Gadea, A.; Giaz, A.; Gottardo, A.; Grave, X.; Grȩbosz, J.; Görgen, A.; Gulmini, M.; Habermann, T.; Hess, H.; Isocrate, R.; Iwanicki, J.; Jaworski, G.; Judson, D. S.; Jungclaus, A.; Karkour, N.; Kmiecik, M.; Karpiński, D.; Kisieliński, M.; Kondratyev, N.; Korichi, A.; Komorowska, M.; Kowalczyk, M.; Korten, W.; Krzysiek, M.; Lehaut, G.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Lunardi, S.; Maron, G.; Mazurek, K.; Menegazzo, R.; Mengoni, D.; Merchán, E.; Mȩczyński, W.; Michelagnoli, C.; Mierzejewski, J.; Million, B.; Myalski, S.; Napoli, D. R.; Nicolini, R.; Niikura, M.; Obertelli, A.; Özmen, S. F.; Palacz, M.; Próchniak, L.; Pullia, A.; Quintana, B.; Rampazzo, G.; Recchia, F.; Redon, N.; Reiter, P.; Rosso, D.; Rusek, K.; Sahin, E.; Salsac, M.-D.; Söderström, P.-A.; Stefan, I.; Stézowski, O.; Styczeń, J.; Theisen, Ch.; Toniolo, N.; Ur, C. A.; Vandone, V.; Wadsworth, R.; Wasilewska, B.; Wiens, A.; Wood, J. L.; Wrzosek-Lipska, K.; Ziȩbliński, M. in Phys. Rev. Lett. (2016). 117(6) 062501.
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NUCLEAR RESONANCE FLUORESCENCE EXPERIMENTS AT ELI-NP. Ur, C. A.; Zilges, A.; Pietralla, N.; Beller, J.; Boisdeffre, B.; Cernaianu, M. O.; Derya, V.; Loeher, B.; Matei, C.; Pascovici, G.; Petcu, C.; Romig, C.; Savran, D.; Suliman, G.; Udup, E.; Werner, V. in ROMANIAN REPORTS IN PHYSICS (2016). 68(2) S483-S538.
The development at ELI-NP of a new laser-based Inverse Compton Scattering gamma beam system, featuring extremely high intensities at very narrow bandwidths, opens new and important opportunities in nuclear science research. Nuclear photonics is undergoing a revival, the gamma beams with unprecedented features delivered at ELI-NP paving the way for high accuracy and detailed nuclear physics studies. A wide range of industrial, homeland security and healthcare applications will also experience an important boost. The combination of nuclear photonics with the technique of Nuclear Resonance Fluorescence (NRF) allows for the recovery of several physical quantities characterizing the excited nuclear states in a completely model independent way. These observables include the excitation energies, level widths, gamma decay branching ratios, spin quantum numbers, and parities. In the last decade, the NRF technique allowed for the discovery and detailed study of various phenomena in atomic nuclei. Examples are the collective magnetic dipole Scissors Mode in deformed nuclei, quadrupole excitations with mixed proton neutron symmetry, the electric Pygmy Dipole Resonance, octupole coupled excitations, or alpha-cluster states. The present Technical Design Report (TDR) deals with the application of the NRF technique at ELI-NP to study forefront nuclear structure research topics. The document presents some of the physics cases to be investigated and discusses the feasibility of the proposed experiments. The advanced characteristics of the gamma beams available at ELI-NP and the use of high efficiency detection systems will offer a powerful combination, unique in the world, for the investigation of the proposed physics cases. The main detection system for the NRF studies is a multi-detector array (ELIADE - ELI-NP Array of DEtectors) based on the use of composite high-purity Ge detectors and large volume LaBr3 scintillator detectors able to detect with high efficiency gamma rays with energies up to several MeV in the presence of the high radiation background produced by the gamma beams. Gamma-ray energies and angular distributions will be measured with high accuracy. The design of the array is made highly flexible to allow for an easy transposition in different locations in the high- and low-energy gamma beam areas, a fast change of configuration based on the needs of the experiments, the use of the detectors in other setups and easy maintenance to reduce the downtimes. NRF measurements will be possible starting from early stages of the Gamma Beam System operation at ELI-NP with both low- and high-energy gamma beams. Already in the initial phase of operation at low-energies below 3.5 MeV the gamma beams at ELI-NP will be competitive with the present state-of-the-art gamma beam systems.
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Low-energy Coulomb excitation of 96,98Sr beams. Clément, E.; Zielińska, M.; Péru, S.; Goutte, H.; Hilaire, S.; Görgen, A.; Korten, W.; Doherty, D. T.; Bastin, B.; Bauer, C.; Blazhev, A.; Bree, N.; Bruyneel, B.; Butler, P. A.; Butterworth, J.; Cederkäll, J.; Delahaye, P.; Dijon, A.; Ekström, A.; Fitzpatrick, C.; Fransen, C.; Georgiev, G.; Gernhäuser, R.; Hess, H.; Iwanicki, J.; Jenkins, D. G.; Larsen, A. C.; Ljungvall, J.; Lutter, R.; Marley, P.; Moschner, K.; Napiorkowski, P. J.; Pakarinen, J.; Petts, A.; Reiter, P.; Renstrøm, T.; Seidlitz, M.; Siebeck, B.; Siem, S.; Sotty, C.; Srebrny, J.; Stefanescu, I.; Tveten, G. M.; Van de Walle, J.; Vermeulen, M.; Voulot, D.; Warr, N.; Wenander, F.; Wiens, A.; De Witte, H.; Wrzosek-Lipska, K. in Phys. Rev. C (2016). 94(5) 054326.
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Low-spin structure of 86Br and 86Kr nuclei: The role of the g7/2 neutron orbital. Urban, W.; Sieja, K.; Materna, T.; Czerwiński, M.; Rząca-Urban, T.; Blanc, A.; Jentschel, M.; Mutti, P.; Köster, U.; Soldner, T.; de France, G.; Simpson, G. S.; Ur, C. A.; Bernards, C.; Fransen, C.; Jolie, J.; Regis, J.-M.; Thomas, T.; Warr, N. in Phys. Rev. C (2016). 94(4) 044328.
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Spectroscopic Quadrupole Moments in 96,98Sr: Evidence for Shape Coexistence in Neutron-Rich Strontium Isotopes at N=60. Clément, E.; Zielińska, M.; Görgen, A.; Korten, W.; Péru, S.; Libert, J.; Goutte, H.; Hilaire, S.; Bastin, B.; Bauer, C.; Blazhev, A.; Bree, N.; Bruyneel, B.; Butler, P. A.; Butterworth, J.; Delahaye, P.; Dijon, A.; Doherty, D. T.; Ekström, A.; Fitzpatrick, C.; Fransen, C.; Georgiev, G.; Gernhäuser, R.; Hess, H.; Iwanicki, J.; Jenkins, D. G.; Larsen, A. C.; Ljungvall, J.; Lutter, R.; Marley, P.; Moschner, K.; Napiorkowski, P. J.; Pakarinen, J.; Petts, A.; Reiter, P.; Renstrøm, T.; Seidlitz, M.; Siebeck, B.; Siem, S.; Sotty, C.; Srebrny, J.; Stefanescu, I.; Tveten, G. M.; Van de Walle, J.; Vermeulen, M.; Voulot, D.; Warr, N.; Wenander, F.; Wiens, A.; De Witte, H.; Wrzosek-Lipska, K in Phys. Rev. Lett. (2016). 116(2) 022701.
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Collective 2+1 excitations in 206Po and 208,210Rn. Grahn, T.; Pakarinen, J.; Jokiniemi, L.; Albers, M.; Auranen, K.; Bauer, C.; Bernards, C.; Blazhev, A.; Butler, P. A.; Bönig, S.; Damyanova, A.; Coster, T. De; Witte, H. De; Elseviers, J.; Gaffney, L. P.; Huyse, M.; Herzáň, A.; Jakobsson, U.; Julin, R.; Kesteloot, N.; Konki, J.; Kröll, Th.; Lewandowski, L.; Moschner, K.; Peura, P.; Pfeiffer, M.; Radeck, D.; Rahkila, P.; Rapisarda, E.; Reiter, P.; Reynders, K.; Rudiger, M.; Salsac, M. D.; Sambi, S.; Scheck, M.; Seidlitz, M.; Siebeck, B.; Steinbach, T.; Stolze, S.; Suhonen, J.; Thoele, P.; Thürauf, M.; Warr, N.; Duppen, P. Van; Venhart, M.; Vermeulen, M. J.; Werner, V.; Veselsky, M.; Vogt, A.; Wrzosek-Lipska, K.; Zielińska, M. in The European Physical Journal A (2016). 52(11)
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Role of the Δ Resonance in the Population of a Four-Nucleon State in the 56Fe→54Fe Reaction at Relativistic Energies. Podolyák, Zs.; Shand, C. M.; Lalović, N.; Gerl, J.; Rudolph, D.; Alexander, T.; Boutachkov, P.; Cortés, M. L.; Górska, M.; Kojouharov, I.; Kurz, N.; Louchart, C.; Merchán, E.; Michelagnoli, C.; Pérez-Vidal, R. M.; Pietri, S.; Ralet, D.; Reese, M.; Schaffner, H.; Stahl, Ch.; Weick, H.; Ameil, F.; de Angelis, G.; Arici, T.; Carroll, R.; Dombrádi, Zs.; Gadea, A.; Golubev, P.; Lettmann, M.; Lizarazo, C.; Mahboub, D.; Pai, H.; Patel, Z.; Pietralla, N.; Regan, P. H.; Sarmiento, L. G.; Wieland, O.; Wilson, E.; Birkenbach, B.; Bruyneel, B.; Burrows, I.; Charles, L.; Clément, E.; Crespi, F. C. L.; Cullen, D. M.; Désesquelles, P.; Eberth, J.; González, V.; Habermann, T.; Harkness-Brennan, L.; Hess, H.; Judson, D. S.; Jungclaus, A.; Korten, W.; Labiche, M.; Maj, A.; Mengoni, D.; Napoli, D. R.; Pullia, A.; Quintana, B.; Rainovski, G.; Reiter, P.; Salsac, M. D.; Sanchis, E.; Valiente Dóbon, J. J. in Phys. Rev. Lett. (2016). 117(22) 222302.
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γ-ray spectroscopy of 33P and 33S after fusion-evaporation reactions. Fu, B.; Seidlitz, M.; Blazhev, A.; Bouhelal, M.; Haas, F.; Reiter, P.; Arnswald, K.; Birkenbach, B.; Fransen, C.; Friessner, G.; Hennig, A.; Hess, H.; Hirsch, R.; Lewandowski, L.; Schneiders, D.; Siebeck, B.; Steinbach, T.; Thomas, T.; Vogt, A.; Wendt, A.; Wolf, K.; Zell, K. O. in Phys. Rev. C (2016). 94(3) 034318.
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Constraints on the α+nucleus optical-model potential via α-induced reaction studies on 108Cd. Scholz, P.; Heim, F.; Mayer, J.; Münker, C.; Netterdon, L.; Wombacher, F.; Zilges, A. in Physics Letters B (2016). 761 247 - 252.
Abstract A big part in understanding the nucleosynthesis of heavy nuclei is a proper description of the effective interaction between an α-particle and a target nucleus. Information about the so-called α+nucleus optical-model potential is achieved by precise cross-section measurements at sub-Coulomb energies aiming to constrain the theoretical models for the nuclear physics input-parameters. The cross sections of the 108Cd(α,γ) and 108Cd(α,n) reaction have been measured for the first time close to the astrophysically relevant energy region via the in-beam method at the high-efficiency γ-ray spectrometer HORUS and via the activation technique at the Cologne Clover Counting Setup at the Institute for Nuclear Physics in Cologne, Germany. Comparisons between experimental results and theoretical predictions calculated in the scope of the Hauser–Feshbach statistical model confirm the need for a exponentially decreasing imaginary part of the potential. Moreover, it is shown that the results presented here together with already published data indicate that a systematic investigation of the real part of the potential could help to further improve the understanding of reactions involving α-particles.
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The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus 133Sb. Bocchi, G.; Leoni, S.; Fornal, B.; Colò, G.; Bortignon, P.F.; Bottoni, S.; Bracco, A.; Michelagnoli, C.; Bazzacco, D.; Blanc, A.; de France, G.; Jentschel, M.; Köster, U.; Mutti, P.; Régis, J.-M.; Simpson, G.; Soldner, T.; Ur, C.A.; Urban, W.; Fraile, L.M.; Lozeva, R.; Belvito, B.; Benzoni, G.; Bruce, A.; Carroll, R.; Cieplicka-Oryǹczak, N.; Crespi, F.C.L.; Didierjean, F.; Jolie, J.; Korten, W.; Kröll, T.; Lalkovski, S.; Mach, H.; Mărginean, N.; Melon, B.; Mengoni, D.; Million, B.; Nannini, A.; Napoli, D.; Olaizola, B.; Paziy, V.; Podolyák, Zs.; Regan, P.H.; Saed-Samii, N.; Szpak, B.; Vedia, V. in Physics Letters B (2016). 760 273 - 278.
Abstract The γ-ray decay of excited states of the one-valence-proton nucleus 133Sb has been studied using cold-neutron induced fission of 235U and 241Pu targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between γ-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 μs isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr3(Ce) scintillators, revealed a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus 132Sn and the valence proton, using the Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin.
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Precise measurement of energies in 115Sn following the (n,γ) reaction. Urban, W.; Köster, U.; Jentschel, M.; Mutti, P.; Märkisch, B.; Rząca-Urban, T.; Bernards, Ch.; Fransen, Ch.; Jolie, J.; Thomas, T.; Simpson, G. S. in Phys. Rev. C (2016). 94(1) 011302.
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On the time response of background obtained in γ-ray spectroscopy experiments using LaBr3(Ce) detectors with different shielding. Régis, J.-M.; Dannhoff, M.; Jolie, J.; Müller-Gatermann, C.; Saed-Samii, N. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2016). 811 42 - 48.
Abstract Employing the γ-γ fast-timing technique with LaBr3(Ce) scintillator detectors allows the direct determination of lifetimes of nuclear excited states with a lower limit of about 5ps. This limit is increased as soon as background is present in the coincidence spectra underneath the full-energy peaks of the γ-γ cascade. Our aim was to identify the components of the γ-ray background by systematic γ-γ fast-timing measurements using different types of γ shielding within a large γ-ray spectrometer. The energy dependent physical zero-time response was measured using background-free full-energy peak events from the 152Eu γ-ray source. This is compared with the time response of the (Compton-) background distribution as obtained using the prompt 60Co γ-ray source. The time response of the typical Compton background is about 15ps faster than the time response of background-free full-energy peak events. Below about 500keV, a second type of background contributes by the detection of Compton-scattered γ rays generated in the materials of the spectrometer around the detector. Due to the additional time-of-flight of the Compton-scattered γ rays, this low-energy background is largely delayed. Compared with a bare cylindrical 1.5in.×1.5in. LaBr3(Ce) detector, the BGO-shielded detector in the Compton-suppression mode improves the peak-to-total ratio by a factor of 1.66(5), while the Pb-shielded detector only slightly reduces the low-energy background.
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Nuclear structure of 96,98Mo: Shape coexistence and mixed-symmetry states. Thomas, T.; Werner, V.; Jolie, J.; Nomura, K.; Ahn, T.; Cooper, N.; Duckwitz, H.; Fitzler, A.; Fransen, C.; Gade, A.; Hinton, M.; Ilie, G.; Jessen, K.; Linnemann, A.; Petkov, P.; Pietralla, N.; Radeck, D. in Nuclear Physics A (2016). 947 203 - 233.
Abstract Excited low-spin states in 96Mo and 98Mo have been studied in γγ angular correlation experiments in order to determine spins and multipole mixing ratios. Furthermore, from a Doppler lineshape analysis effective lifetimes τ in the femtosecond range were obtained. The experimental data show a complex spectrum due to configuration mixing, which is confirmed by Interacting Boson Model calculations based on a Skyrme energy density functional. The M1-transition strengths of transitions depopulating excited 2+ states to the first 2+ state are discussed in terms of the proton–neutron mixed symmetry.
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Magnetic dipole excitations of 50Cr. Pai, H.; Beck, T.; Beller, J.; Beyer, R.; Bhike, M.; Derya, V.; Gayer, U.; Isaak, J.; Krishichayan,; Kvasil, J.; Löher, B.; Nesterenko, V. O.; Pietralla, N.; Martínez-Pinedo, G.; Mertes, L.; Ponomarev, V. Yu.; Reinhard, P.-G.; Repko, A.; Ries, P. C.; Romig, C.; Savran, D.; Schwengner, R.; Tornow, W.; Werner, V.; Wilhelmy, J.; Zilges, A.; Zweidinger, M. in Phys. Rev. C (2016). 93(1) 014318.
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Coulomb dissociation of N-20,N-21. Roeder, Marko; Adachi, Tatsuya; Aksyutina, Yulia; Alcantara, Juan; Altstadt, Sebastian; Alvarez-Pol, Hector; Ashwood, Nicholas; Atar, Leyla; Aumann, Thomas; Avdeichikov, Vladimir; Barr, M.; Beceiro, Saul; Bemmerer, Daniel; Benlliure, Jose; Bertulani, Carlos; Boretzky, Konstanze; Borge, Maria J. G.; Burgunder, G.; Caamano, Manuel; Caesar, Christoph; Casarejos, Enrique; Catford, Wilton; Cederkall, Joakim; Chakraborty, S.; Chartier, Marielle; Chulkov, Leonid; Cortina-Gil, Dolores; Crespo, Raquel; Pramanik, Ushasi Datta; Diaz-Fernandez, Paloma; Dillmann, Iris; Elekes, Zoltan; Enders, Joachim; Ershova, Olga; Estrade, A.; Farinon, F.; Fraile, Luis M.; Freer, Martin; Freudenberger, M.; Fynbo, Hans; Galaviz, Daniel; Geissel, Hans; Gernhaeuser, Roman; Goebel, Kathrin; Golubev, Pavel; Diaz, D. Gonzalez; Hagdahl, Julius; Heftrich, Tanja; Heil, Michael; Heine, Marcel; Heinz, Andreas; Henriques, Ana; Holl, Matthias; Ickert, G.; Ignatov, Alexander; Jakobsson, Bo; Johansson, Hakan; Jonson, Bjorn; Kalantar-Nayestanaki, Nasser; Kanungo, Rituparna; Kelic-Heil, Aleksandra; Knoebel, Ronja; Kroell, Thorsten; Kruecken, Reiner; Kurcewicz, J.; Kurz, Nikolaus; Labiche, Marc; Langer, Christoph; Le Bleis, Tudi; Lemmon, Roy; Lepyoshkina, Olga; Lindberg, Simon; Machado, Jorge; Marganiec, Justyna; Mostazo Caro, Magdalena; Movsesyan, Alina; Najafi, Mohammad Ali; Nilsson, Thomas; Nociforo, Chiara; Panin, Valerii; Paschalis, Stefanos; Perea, Angel; Petri, Marina; Pietri, S.; Plag, Ralf; Prochazka, A.; Rahaman, Md. Anisur; Rastrepina, Ganna; Reifarth, Rene; Ribeiro, Guillermo; Ricciardi, M. Valentina; Rigollet, Catherine; Riisager, Karsten; Rossi, Dominic; del Rio Saez, Jose Sanchez; Savran, Deniz; Scheit, Heiko; Simon, Haik; Sorlin, Olivier; Stoica, V.; Streicher, Branislav; Taylor, Jon; Tengblad, Olof; Terashima, Satoru; Thies, Ronja; Togano, Yasuhiro; Uberseder, Ethan; Van de Walle, J.; Velho, Paulo; Volkov, Vasily; Wagner, Andreas; Wamers, Felix; Weick, Helmut; Weigand, Mario; Wheldon, Carl; Wilson, G.; Wimmer, Christine; Winfield, J. S.; Woods, Philip; Yakorev, Dmitry; Zhukov, Mikhail; Zilges, Andreas; Zuber, Kai; Collaboration, R3B in Phys. Rev. C (2016). 93(6)
Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N-20,N-21 are reported. Relativistic N-20,N-21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the N-19(n,gamma)N-20 and N-20(n,gamma)N-21 excitation functions and thermonuclear reaction rates have been determined. The N-19(n,gamma)N-20 rate is up to a factor of 5 higher at T < 1 GK with respect to previous theoretical calculations, leading to a 10% decrease in the predicted fluorine abundance.
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Decay of quadrupole-octupole 1(-) states in Ca-40 and Ce-140. Derya, V.; Tsoneva, N.; Aumann, T.; Bhike, M.; Endres, J.; Gooden, M.; Hennig, A.; Isaak, J.; Lenske, H.; Loeher, B.; Pietralla, N.; Savran, D.; Tornow, W.; Werner, V.; Zilges, A. in Phys. Rev. C (2016). 93(3)
Background: Two-phonon excitations originating from the coupling of two collective one-phonon states are of great interest in nuclear structure physics. One possibility to generate low-lying E1 excitations is the coupling of quadrupole and octupole phonons. Purpose: In this work, the gamma-decay behavior of candidates for the (2(1)(+) circle times 3(1))(1)-state in the doubly magic nucleus Ca-40 and in the heavier and semimagic nucleus Ce-140 is investigated. Methods: ((gamma) over bar,gamma') experiments have been carried out at the High Intensity gamma-ray Source (HI gamma S) facility in combination with the high-efficiency gamma-ray spectroscopy setup gamma(3) consisting of HPGe and LaBr3 detectors. The setup enables the acquisition of gamma-gamma coincidence data and, hence, the detection of direct decay paths. Results: In addition to the known ground-state decays, for Ca-40 the decay into the 3(1) state was observed, while for Ce-140 the direct decays into the 2(1)(+) and the 0(2)(+) state were detected. The experimentally deduced transition strengths and excitation energies are compared to theoretical calculations in the framework of EDF theory plus QPM approach and systematically analyzed for N = 82 isotones. In addition, negative parities for two J = 1 states in Ca-44 were deduced simultaneously. Conclusions: The experimental findings together with the theoretical calculations support the two-phonon character of the 1(1)(-) excitation in the light-to-medium-mass nucleus Ca-40 as well as in the stable even-even N = 82 nuclei.
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Finite valence nucleon number and rotation-vibration interactions. Casten, R. F.; Jolie, J.; Cakirli, R. B.; Couture, A. in Phys. Rev. C (2016). 94(6) 061303.
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Magnetic dipole excitations of Cr-50. Pai, H.; Beck, T.; Beller, J.; Beyer, R.; Bhike, M.; Derya, V.; Gayer, U.; Isaak, J.; Krishichayan,; Kvasil, J.; Loeher, B.; Nesterenko, V. O.; Pietralla, N.; Martinez-Pinedo, G.; Mertes, L.; Ponomarev, V. Yu; Reinhard, P. G.; Repko, A.; Ries, P. C.; Romig, C.; Savran, D.; Schwengner, R.; Tornow, W.; Werner, V.; Wilhelmy, J.; Zilges, A.; Zweidinger, M. in Phys. Rev. C (2016). 93(1)
The low-lying M1 strength of the open-shell nucleus Cr-50 has been studied with the method of nuclear resonance fluorescence up to 9.7 MeV using bremsstrahlung at the superconducting Darmstadt linear electron accelerator S-DALINAC and Compton backscattered photons at the High Intensity gamma-ray Source (HI gamma S) facility between 6 and 9.7 MeV of the initial photon energy. Fifteen 1(+) states have been observed between 3.6 and 9.7 MeV. Following our analysis the lowest 1(+) state at 3.6 MeV can be considered as an isovector orbital mode with some spin admixture. The obtained results generally match the estimations and trends typical for the scissors-like mode. Detailed calculations within the Skyrme quasiparticle random-phase-approximation method and the large-scale shell model justify our conclusions. The calculated distributions of the orbital current for the lowest 1(+)-state suggest the schematic view of Lipparini and Stringari (isovector rotation-like oscillations inside the rigid surface) rather than the scissors-like picture of Lo Iudice and Palumbo. The spin M1 resonance is shown to be mainly generated by spin-flip transitions between the orbitals of the fp shell.
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Spin Physics and Polarized Fusion: Where We Stand. Paetz gen. Schieck, Hans in Springer Proceedings in Physics, G. Ciullo, Engels, R., Büscher, M., Vasilyev, A. (Hrsg.) (2016). (Bd. 187)
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Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes. Thies, R.; Heinz, A.; Adachi, T.; Aksyutina, Y.; Alcantara-Núñes, J.; Altstadt, S.; Alvarez-Pol, H.; Ashwood, N.; Aumann, T.; Avdeichikov, V.; Barr, M.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Burgunder, G.; Camaño, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkäll, J.; Chakraborty, S.; Chartier, M.; Chulkov, L. V.; Cortina-Gil, D.; Crespo, R.; Datta, U.; Díaz Fernández, P.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estradé, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Freudenberger, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhäuser, R.; Göbel, K.; Golubev, P.; Gonzalez Diaz, D.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Henriques, A.; Holl, M.; Ickert, G.; Ignatov, A.; Jakobsson, B.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Knöbel, R.; Kröll, T.; Krücken, R.; Kurcewicz, J.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lepyoshkina, O.; Lindberg, S.; Machado, J.; Marganiec, J.; Maroussov, V.; Mostazo, M.; Movsesyan, A.; Najafi, A.; Nilsson, T.; Nociforo, C.; Panin, V.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Prochazka, A.; Rahaman, A.; Rastrepina, G.; Reifarth, R.; Ribeiro, G.; Ricciardi, M. V.; Rigollet, C.; Riisager, K.; Röder, M.; Rossi, D.; Sanchez del Rio, J.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Stoica, V.; Streicher, B.; Taylor, J. T.; Tengblad, O.; Terashima, S.; Togano, Y.; Uberseder, E.; Van de Walle, J.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Weigand, M.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M. V.; Zilges, A.; Zuber, K. in Phys. Rev. C (2016). 93(5) 054601.
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Foreword. Paetz gen. Schieck, Hans in Springer Proceedings in Physics, G. Ciullo, Engels, R., Büscher, M., Vasilyev, A. (Hrsg.) (2016). (Bd. 187)
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The PolFusion Experiment: Measurement of the dd-Fusion Spin-Dependence. Vasilyev, Alexander; Kochenda, L.; Kravtsov, P.; Trofimov, V.; Vznudaev, M.; Ciullo, Giuseppe; Lenisa, P.; Engels, Ralf; Paetz gen. Schieck, Hans in Springer Proceedings in Physics, G. Ciullo, Engels, R., Büscher, M., Vasilyev, A. (Hrsg.) (2016). (Bd. 187)
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Hyper-Polarized Deuterium Molecules: An Option to Produce and Store Polarized Fuel for Nuclear Fusion? Engels, R.; Farren, G.; Grigoryev, K.; Mikirtychiants, M.; Rathmann, F.; Seyfarth, H.; Ströher, H.; Kochenda, L.; Kravtsov, P.; Trofimov, V.; Vasilyev, A.; Vznudaev, M.; Paetz gen. Schieck, H. in Nuclear Fusion with Polarized Fuel, G. Ciullo, Engels, R., Büscher, M., Vasilyev, A. (Hrsg.) (2016).
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Structure of low-lying states in 140Sm studied by Coulomb excitation. Klintefjord, M.; Hadyńska-Klȩk, K.; Görgen, A.; Bauer, C.; Bello Garrote, F. L.; Bönig, S.; Bounthong, B.; Damyanova, A.; Delaroche, J.-P.; Fedosseev, V.; Fink, D. A.; Giacoppo, F.; Girod, M.; Hoff, P.; Imai, N.; Korten, W.; Larsen, A.-C.; Libert, J.; Lutter, R.; Marsh, B. A.; Molkanov, P. L.; Naïdja, H.; Napiorkowski, P.; Nowacki, F.; Pakarinen, J.; Rapisarda, E.; Reiter, P.; Renstrøm, T.; Rothe, S.; Seliverstov, M. D.; Siebeck, B.; Siem, S.; Srebrny, J.; Stora, T.; Thöle, P.; Tornyi, T. G.; Tveten, G. M.; Van Duppen, P.; Vermeulen, M. J.; Voulot, D.; Warr, N.; Wenander, F.; De Witte, H.; Zielińska, M. in Phys. Rev. C (2016). 93(5) 054303.
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Spectroscopy of 46Ar by the (t,p) two-neutron transfer reaction. Nowak, K.; Wimmer, K.; Hellgartner, S.; Mücher, D.; Bildstein, V.; Diriken, J.; Elseviers, J.; Gaffney, L. P.; Gernhäuser, R.; Iwanicki, J.; Johansen, J. G.; Huyse, M.; Konki, J.; Kröll, T.; Krücken, R.; Lutter, R.; Orlandi, R.; Pakarinen, J.; Raabe, R.; Reiter, P.; Roger, T.; Schrieder, G.; Seidlitz, M.; Sorlin, O.; Van Duppen, P.; Warr, N.; De Witte, H.; Zielińska, M. in Phys. Rev. C (2016). 93(4) 044335.
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Pygmy dipole resonance in 140Ce via inelastic scattering of 17O. Krzysiek, M.; Kmiecik, M.; Maj, A.; Bednarczyk, P.; Bracco, A.; Crespi, F. C. L.; Lanza, E. G.; Litvinova, E.; Paar, N.; Avigo, R.; Bazzacco, D.; Benzoni, G.; Birkenbach, B.; Blasi, N.; Bottoni, S.; Brambilla, S.; Camera, F.; Ceruti, S.; Ciemała, M.; de Angelis, G.; Désesquelles, P.; Eberth, J.; Farnea, E.; Gadea, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Grębosz, J.; Hess, H.; Isocarte, R.; Jungclaus, A.; Leoni, S.; Ljungvall, J.; Lunardi, S.; Mazurek, K.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Milion, B.; Morales, A. I.; Napoli, D. R.; Nicolini, R.; Pellegri, L.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Rosso, D.; Salsac, M. D.; Siebeck, B.; Siem, S.; Söderström, P.-A.; Ur, C.; Valiente-Dobon, J. J.; Wieland, O.; Ziębliński, M. in Phys. Rev. C (2016). 93(4) 044330.
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Partial cross sections of the 92Mo(p,γ) reaction and the γ strength in 93Tc. Mayer, J.; Goriely, S.; Netterdon, L.; Péru, S.; Scholz, P.; Schwengner, R.; Zilges, A. in Phys. Rev. C (2016). 93(4) 045809.
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Evolution of collectivity near mid-shell from excited-state lifetime measurements in rare earth nuclei. Werner, V.; Cooper, N.; Régis, J.-M.; Rudigier, M.; Williams, E.; Jolie, J.; Cakirli, R. B.; Casten, R. F.; Ahn, T.; Anagnostatou, V.; Berant, Z.; Bonett-Matiz, M.; Elvers, M.; Heinz, A.; Ilie, G.; Radeck, D.; Savran, D.; Smith, M. K. in Phys. Rev. C (2016). 93(3) 034323.
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Systematic investigation of projectile fragmentation using beams of unstable B and C isotopes. Thies, R.; Heinz, A.; Adachi, T.; Aksyutina, Y.; Alcantara-Nunes, J.; Altstadt, S.; Alvarez-Pol, H.; Ashwood, N.; Aumann, T.; Avdeichikov, V.; Barr, M.; Beceiro-Novo, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Burgunder, G.; Camano, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkall, J.; Chakraborty, S.; Chartier, M.; Chulkov, L. V.; Cortina-Gil, D.; Crespo, R.; Datta, U.; Diaz Fernandez, P.; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Freudenberger, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhauser, R.; Gobel, K.; Golubev, P.; Diaz, D. Gonzalez; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Henriques, A.; Holl, M.; Ickert, G.; Ignatov, A.; Jakobsson, B.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Knobel, R.; Kroll, T.; Krucken, R.; Kurcewicz, J.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lepyoshkina, O.; Lindberg, S.; Machado, J.; Marganiec, J.; Maroussov, V.; Mostazo, M.; Movsesyan, A.; Najafi, A.; Nilsson, T.; Nociforo, C.; Panin, V.; Paschalis, S.; Perea, A.; Petri, M.; Pietri, S.; Plag, R.; Prochazka, A.; Rahaman, A.; Rastrepina, G.; Reifarth, R.; Ribeiro, G.; Ricciardi, M. V.; Rigollet, C.; Riisager, K.; Roder, M.; Rossi, D.; Sanchez del Rio, J.; Savran, D.; Scheit, H.; Simon, H.; Sorlin, O.; Stoica, V.; Streicher, B.; Taylor, J. T.; Tengblad, O.; Terashima, S.; Togano, Y.; Uberseder, E.; Van de Walle, J.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Weigand, M.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M. V.; Zilges, A.; Zuber, K.; Collaboration, R3B in Phys. Rev. C (2016). 93(5)
Background: Models describing nuclear fragmentation and fragmentation fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool for reaching the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from (10,12-18C) and B10-15 isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent data set. We compare our data to model calculations. Results: One-proton removal cross sections with different final neutron numbers (1 pxn) for relativistic C-10,C-12-18 and B10-15 isotopes impinging on a carbon target. Comparing model calculations to the data, we find that the EPAX code is not able to describe the data satisfactorily. Using ABRABLA07 on the other hand, we find that the average excitation energy per abraded nucleon needs to be decreased from 27 MeV to 8.1 MeV. With that decrease ABRABLA07 describes the data surprisingly well. Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data has allowed a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Most striking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless, this parameter, which has been related to final-state interactions, requires further study.
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Reduced γ–γ time walk to below 50 ps using the multiplexed-start and multiplexed-stop fast-timing technique with LaBr3(Ce) detectors. Régis, J.-M.; Saed-Samii, N.; Rudigier, M.; Ansari, S.; Dannhoff, M.; Esmaylzadeh, A.; Fransen, C.; Gerst, R.-B.; Jolie, J.; Karayonchev, V.; Müller-Gatermann, C.; Stegemann, S. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2016). 823 72 - 82.
Abstract The electronic γ–γ fast-timing technique using arrays consisting of many LaBr3(Ce) detectors is a powerful method to determine lifetimes of nuclear excited states with a lower limit of about 5ps. This method requires the determination of the energy-dependent time walk of the zero time which is represented by the centroid of a prompt γ–γ time distribution. The full-energy peak versus full-energy peak prompt response difference which represents the linearly combined mean γ–γ time walk of a fast-timing array consisting of 8 LaBr3(Ce) detectors was measured using a standard 152Eu γ-ray source for the energy region of 40–1408keV. The data were acquired using a “multiplexed-start and multiplexed-stop” analogue electronics circuitry and analysed by employing the generalized centroid difference method. Concerning the cylindrical 1.5in.×1.5in. LaBr3(Ce) crystals which are coupled to the Hamamatsu R9779 photomultiplier tubes, the best fast-timing array time resolution of 202(3)ps is obtained for the two prompt γ lines of 60Co by using the leading-edge timing principle. When using the zero-crossover timing principle the time resolution is degraded by up to 30%, dependent on the energy and the shaping delay time of the constant fraction discriminator model Ortec 935. The smallest γ–γ time walk to below 50ps is obtained by using a shaping delay time of about 17ns and an optimum “time-walk adjustment” needed for detector output pulses with amplitudes smaller than 400mV.
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Low-lying isovector 2+ valence-shell excitations of 212Po. Kocheva, D.; Rainovski, G.; Jolie, J.; Pietralla, N.; Stahl, C.; Petkov, P.; Blazhev, A.; Hennig, A.; Astier, A.; Braunroth, Th.; Cortés, M. L.; Dewald, A.; Djongolov, M.; Fransen, C.; Gladnishki, K.; Karayonchev, V.; Litzinger, J.; Müller-Gatermann, C.; Scheck, M.; Scholz, Ph.; Stegmann, R.; Thöle, P.; Werner, V.; Witt, W.; Wölk, D.; Van Isacker, P. in Phys. Rev. C (2016). 93(1) 011303.
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The decay pattern of the Pygmy Dipole Resonance of 140Ce. Löher, B.; Savran, D.; Aumann, T.; Beller, J.; Bhike, M.; Cooper, N.; Derya, V.; Duchêne, M.; Endres, J.; Hennig, A.; Humby, P.; Isaak, J.; Kelley, J.H.; Knörzer, M.; Pietralla, N.; Ponomarev, V.Yu.; Romig, C.; Scheck, M.; Scheit, H.; Silva, J.; Tonchev, A.P.; Tornow, W.; Wamers, F.; Weller, H.; Werner, V.; Zilges, A. in Physics Letters B (2016). 756 72 - 76.
Abstract The decay properties of the Pygmy Dipole Resonance (PDR) have been investigated in the semi-magic N=82 nucleus 140Ce using a novel combination of nuclear resonance fluorescence and γ–γ coincidence techniques. Branching ratios for transitions to low-lying excited states are determined in a direct and model-independent way both for individual excited states and for excitation energy intervals. Comparison of the experimental results to microscopic calculations in the quasi-particle phonon model exhibits an excellent agreement, supporting the observation that the Pygmy Dipole Resonance couples to the ground state as well as to low-lying excited states. A 10% mixing of the PDR and the [21+×PDR] is extracted.
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High-spin structure of 134Xe. Vogt, A.; Birkenbach, B.; Reiter, P.; Blazhev, A.; Siciliano, M.; Valiente-Dobón, J. J.; Wheldon, C.; Bazzacco, D.; Bowry, M.; Bracco, A.; Bruyneel, B.; Chakrawarthy, R. S.; Chapman, R.; Cline, D.; Corradi, L.; Crespi, F. C. L.; Cromaz, M.; de Angelis, G.; Eberth, J.; Fallon, P.; Farnea, E.; Fioretto, E.; Freeman, S. J.; Gadea, A.; Geibel, K.; Gelletly, W.; Gengelbach, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Hayes, A. B.; Hess, H.; Hua, H.; John, P. R.; Jolie, J.; Jungclaus, A.; Korten, W.; Lee, I. Y.; Leoni, S.; Liang, X.; Lunardi, S.; Macchiavelli, A. O.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Napoli, D.; Pearson, C. J.; Pellegri, L.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Radeck, F.; Recchia, F.; Regan, P. H.; Şahin, E.; Scarlassara, F.; Sletten, G.; Smith, J. F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szilner, S.; Szpak, B.; Teng, R.; Ur, C.; Vandone, V.; Ward, D.; Warner, D. D.; Wiens, A.; Wu, C. Y. in Phys. Rev. C (2016). 93(5) 054325.
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Measurement of picosecond lifetimes in neutron-rich Xe isotopes. Ilieva, S.; Kröll, Th.; Régis, J.-M.; Saed-Samii, N.; Blanc, A.; Bruce, A. M.; Fraile, L. M.; de France, G.; Hartig, A.-L.; Henrich, C.; Ignatov, A.; Jentschel, M.; Jolie, J.; Korten, W.; Köster, U.; Lalkovski, S.; Lozeva, R.; Mach, H.; Mărginean, N.; Mutti, P.; Paziy, V.; Regan, P. H.; Simpson, G. S.; Soldner, T.; Thürauf, M.; Ur, C. A.; Urban, W.; Warr, N. in Phys. Rev. C (2016). 94(3) 034302.
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Pair neutron transfer in 60Ni+116Sn probed via γ-particle coincidences. Montanari, D.; Corradi, L.; Szilner, S.; Pollarolo, G.; Goasduff, A.; Mijatović, T.; Bazzacco, D.; Birkenbach, B.; Bracco, A.; Charles, L.; Courtin, S.; Désesquelles, P.; Fioretto, E.; Gadea, A.; Görgen, A.; Gottardo, A.; Grebosz, J.; Haas, F.; Hess, H.; Jelavić Malenica, D.; Jungclaus, A.; Karolak, M.; Leoni, S.; Maj, A.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Montagnoli, G.; Napoli, D. R.; Pullia, A.; Recchia, F.; Reiter, P.; Rosso, D.; Salsac, M. D.; Scarlassara, F.; Söderström, P.-A.; Soić, N.; Stefanini, A. M.; Stezowski, O.; Theisen, Ch.; Ur, C. A.; Valiente-Dobón, J. J.; Varga Pajtler, M. in Phys. Rev. C (2016). 93(5) 054623.
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Relativistic Coulomb excitation of 88Kr. Moschner, K.; Blazhev, A.; Jolie, J.; Warr, N.; Boutachkov, P.; Bednarczyk, P.; Sieja, K.; Algora, A.; Ameil, F.; Bentley, M. A.; Brambilla, S.; Braun, N.; Camera, F.; Cederkäll, J.; Corsi, A.; Danchev, M.; DiJulio, D.; Fahlander, C.; Gerl, J.; Giaz, A.; Golubev, P.; Górska, M.; Grebosz, J.; Habermann, T.; Hackstein, M.; Hoischen, R.; Kojouharov, I.; Kurz, N.; Mărginean, N.; Merchán, E.; Möller, T.; Naqvi, F.; Nara Singh, B. S.; Nociforo, C.; Pietralla, N.; Pietri, S.; Podolyák, Zs.; Prochazka, A.; Reese, M.; Reiter, P.; Rudigier, M.; Rudolph, D.; Sava, T.; Schaffner, H.; Scruton, L.; Taprogge, J.; Thomas, T.; Weick, H.; Wendt, A.; Wieland, O.; Wollersheim, H.-J. in Phys. Rev. C (2016). 94(5) 054323.
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The pygmy quadrupole resonance and neutron-skin modes in 124Sn. Spieker, M.; Tsoneva, N.; Derya, V.; Endres, J.; Savran, D.; Harakeh, M.N.; Harissopulos, S.; Herzberg, R.-D.; Lagoyannis, A.; Lenske, H.; Pietralla, N.; Popescu, L.; Scheck, M.; Schlüter, F.; Sonnabend, K.; Stoica, V.I.; Wörtche, H.J.; Zilges, A. in Physics Letters B (2016). 752 102 - 107.
Abstract We present an extensive experimental study of the recently predicted pygmy quadrupole resonance (PQR) in Sn isotopes, where complementary probes were used. In this study, (α,α′γ) and (γ,γ′) experiments were performed on 124Sn. In both reactions, Jπ=2+ states below an excitation energy of 5 MeV were populated. The E2 strength integrated over the full transition densities could be extracted from the (γ,γ′) experiment, while the (α,α′γ) experiment at the chosen kinematics strongly favors the excitation of surface modes because of the strong α-particle absorption in the nuclear interior. The excitation of such modes is in accordance with the quadrupole-type oscillation of the neutron skin predicted by a microscopic approach based on self-consistent density functional theory and the quasiparticle-phonon model (QPM). The newly determined γ-decay branching ratios hint at a non-statistical character of the E2 strength, as it has also been recently pointed out for the case of the pygmy dipole resonance (PDR). This allows us to distinguish between PQR-type and multiphonon excitations and, consequently, supports the recent first experimental indications of a PQR in 124Sn.
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Evolution of quadrupole collectivity in N=80 isotones toward the Z=64 subshell gap: The B(E2;2+1→0+1) value of 142Sm. Stegmann, R.; Bauer, C.; Rainovski, G.; Pietralla, N.; Stahl, C.; Bönig, S.; Ilieva, S.; Blazhev, A.; Damyanova, A.; Danchev, M.; Gladnishki, K.; Jolie, J.; Lutter, R.; Pakarinen, J.; Radeck, D.; Rapisarda, E.; Reiter, P.; Scheck, M.; Siebeck, B.; Stora, T.; Thöle, P.; Thomas, T.; Thürauf, M.; Vermeulen, M. J.; Voulot, D.; Warr, N.; Wenander, F.; Werner, V.; De Witte, H. in Phys. Rev. C (2015). 91(5) 054326.
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Population of the 2+ms mixed-symmetry state of 140Ba with the α-transfer reaction. Stahl, C.; Leske, J.; Bauer, C.; Bazzacco, D.; Farnea, E.; Gottardo, A.; John, P. R.; Michelagnoli, C.; Pietralla, N.; Reese, M.; Şahin, E.; Birkenbach, B.; Bracco, A.; Crespi, F. C. L.; de Angelis, G.; Désesquelles, P.; Eberth, J.; Gadea, A.; Görgen, A.; Grebosz, J.; Hess, H.; Jolie, J.; Jungclaus, A.; Korten, W.; Lenzi, S. M.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Modamio, V.; Napoli, D. R.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Rosso, D.; Salsac, M. D.; Söderström, P.-A.; Stezowski, O.; Theisen, Ch.; Ur, C. A.; Valiente-Dobón, J. J. in Phys. Rev. C (2015). 92(4) 044324.
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Reduced transition strengths of low-lying yrast states in chromium isotopes in the vicinity of N=40. Braunroth, Thomas; Dewald, A.; Iwasaki, H.; Lenzi, S. M.; Albers, M.; Bader, V. M.; Baugher, T.; Baumann, T.; Bazin, D.; Berryman, J. S.; Fransen, C.; Gade, A.; Ginter, T.; Gottardo, A.; Hackstein, M.; Jolie, J.; Lemasson, A.; Litzinger, J.; Lunardi, S.; Marchi, T.; Modamio, V.; Morse, C.; Napoli, D. R.; Nichols, A.; Recchia, F.; Stroberg, S. R.; Wadsworth, R.; Weisshaar, D.; Whitmore, K.; Wimmer, K. in Phys. Rev. C (2015). 92(3) 034306.
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Partial dynamical symmetry in Bose-Fermi systems. Van Isacker, P.; Jolie, J.; Thomas, T.; Leviatan, A. in Phys. Rev. C (2015). 92(1) 011301.
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Low spin structure of 86Se: Confirmation of γ collectivity at N=52. Materna, T.; Urban, W.; Sieja, K.; Köster, U.; Faust, H.; Czerwiński, M.; Rząca-Urban, T.; Bernards, C.; Fransen, C.; Jolie, J.; Regis, J.-M.; Thomas, T.; Warr, N. in Phys. Rev. C (2015). 92(3) 034305.
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97Rb: The Cornerstone of the Region of Deformation around A∼100. Sotty, C.; Zielińska, M.; Georgiev, G.; Balabanski, D. L.; Stuchbery, A. E.; Blazhev, A.; Bree, N.; Chevrier, R.; Das Gupta, S.; Daugas, J. M.; Davinson, T.; De Witte, H.; Diriken, J.; Gaffney, L. P.; Geibel, K.; Hadyńska-Klȩk, K.; Kondev, F. G.; Konki, J.; Kröll, T.; Morel, P.; Napiorkowski, P.; Pakarinen, J.; Reiter, P.; Scheck, M.; Seidlitz, M.; Siebeck, B.; Simpson, G.; Törnqvist, H.; Warr, N.; Wenander, F. in Phys. Rev. Lett. (2015). 115(17) 172501.
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Spectroscopy of the neutron-rich actinide nucleus 240U following multinucleon-transfer reactions. Birkenbach, B.; Vogt, A.; Geibel, K.; Recchia, F.; Reiter, P.; Valiente-Dobón, J. J.; Bazzacco, D.; Bowry, M.; Bracco, A.; Bruyneel, B.; Corradi, L.; Crespi, F. C. L.; de Angelis, G.; Désesquelles, P.; Eberth, J.; Farnea, E.; Fioretto, E.; Gadea, A.; Gengelbach, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Grebosz, J.; Hess, H.; John, P. R.; Jolie, J.; Judson, D. S.; Jungclaus, A.; Korten, W.; Lenzi, S.; Leoni, S.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatović, T.; Montagnoli, G.; Montanari, D.; Napoli, D.; Pellegri, L.; Pollarolo, G.; Pullia, A.; Quintana, B.; Radeck, F.; Rosso, D.; Şahin, E.; Salsac, M. D.; Scarlassara, F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szilner, S.; Szpak, B.; Theisen, Ch.; Ur, C.; Vandone, V.; Wiens, A. in Phys. Rev. C (2015). 92(4) 044319.
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Characterization of different surface passivation routes applied to a planar HPGe detector. Maggioni, G.; Napoli, D. R.; Eberth, J.; Gelain, M.; Carturan, S.; Grimaldi, M. G.; Tatì, S. in The European Physical Journal A (2015). 51(11) 141.
The effects of different passivation methods applied to the same planar high-purity germanium gamma radiation detector have been studied. By means of the scanning with a low-energy collimated gamma source, it has been found that the surface passivation gives rise to a dead layer below the intrinsic Ge surface, whose thickness and distribution are strongly dependent on the passivation type. Measured bulk detector properties like the peak-to-Compton ratio and efficiency have shown a dependence on the passivation and an influence of the passivation type on the depletion voltage, whilst the optimal energy resolution has been the same for all the passivations.
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Deformation and mixing of coexisting shapes in neutron-deficient polonium isotopes. Kesteloot, N.; Bastin, B.; Gaffney, L. P.; Wrzosek-Lipska, K.; Auranen, K.; Bauer, C.; Bender, M.; Bildstein, V.; Blazhev, A.; Bönig, S.; Bree, N.; Clément, E.; Cocolios, T. E.; Damyanova, A.; Darby, I.; De Witte, H.; Di Julio, D.; Diriken, J.; Fransen, C.; García-Ramos, J. E.; Gernhäuser, R.; Grahn, T.; Heenen, P.-H.; Hess, H.; Heyde, K.; Huyse, M.; Iwanicki, J.; Jakobsson, U.; Konki, J.; Kröll, T.; Laurent, B.; Lecesne, N.; Lutter, R.; Pakarinen, J.; Peura, P.; Piselli, E.; Próchniak, L.; Rahkila, P.; Rapisarda, E.; Reiter, P.; Scheck, M.; Seidlitz, M.; Sferrazza, M.; Siebeck, B.; Sjodin, M.; Tornqvist, H.; Traykov, E.; Van De Walle, J.; Van Duppen, P.; Vermeulen, M.; Voulot, D.; Warr, N.; Wenander, F.; Wimmer, K.; Zielińska, M. in Phys. Rev. C (2015). 92(5) 054301.
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Light and heavy transfer products in 136Xe+238U multinucleon transfer reactions. Vogt, A.; Birkenbach, B.; Reiter, P.; Corradi, L.; Mijatović, T.; Montanari, D.; Szilner, S.; Bazzacco, D.; Bowry, M.; Bracco, A.; Bruyneel, B.; Crespi, F. C. L.; de Angelis, G.; Désesquelles, P.; Eberth, J.; Farnea, E.; Fioretto, E.; Gadea, A.; Geibel, K.; Gengelbach, A.; Giaz, A.; Görgen, A.; Gottardo, A.; Grebosz, J.; Hess, H.; John, P. R.; Jolie, J.; Judson, D. S.; Jungclaus, A.; Korten, W.; Leoni, S.; Lunardi, S.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Montagnoli, G.; Napoli, D.; Pellegri, L.; Pollarolo, G.; Pullia, A.; Quintana, B.; Radeck, F.; Recchia, F.; Rosso, D.; Şahin, E.; Salsac, M. D.; Scarlassara, F.; Söderström, P.-A.; Stefanini, A. M.; Steinbach, T.; Stezowski, O.; Szpak, B.; Theisen, Ch.; Ur, C.; Valiente-Dobón, J. J.; Vandone, V.; Wiens, A. in Phys. Rev. C (2015). 92(2) 024619.
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Isospin Mixing in 80Zr: From Finite to Zero Temperature. Ceruti, S.; Camera, F.; Bracco, A.; Avigo, R.; Benzoni, G.; Blasi, N.; Bocchi, G.; Bottoni, S.; Brambilla, S.; Crespi, F. C. L.; Giaz, A.; Leoni, S.; Mentana, A.; Million, B.; Morales, A. I.; Nicolini, R.; Pellegri, L.; Pullia, A.; Riboldi, S.; Wieland, O.; Birkenbach, B.; Bazzacco, D.; Ciemala, M.; Désesquelles, P.; Eberth, J.; Farnea, E.; Görgen, A.; Gottardo, A.; Hess, H.; Judson, D. S.; Jungclaus, A.; Kmiecik, M.; Korten, W.; Maj, A.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Modamio, V.; Montanari, D.; Myalski, S.; Napoli, D.; Quintana, B.; Reiter, P.; Recchia, F.; Rosso, D.; Sahin, E.; Salsac, M. D.; Söderström, P.-A.; Stezowski, O.; Theisen, Ch.; Ur, C.; Valiente-Dobón, J. J.; Zieblinski, M. in Phys. Rev. Lett. (2015). 115(22) 222502.
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Perspectives for photonuclear research at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility. Filipescu, D.; Anzalone, A.; Balabanski, D. L.; Belyshev, S. S.; Camera, F.; La Cognata, M.; Constantin, P.; Csige, L.; Cuong, P. V.; Cwiok, M.; Derya, V.; Dominik, W.; Gai, M.; Gales, S.; Gheorghe, I.; Ishkhanov, B. S.; Krasznahorkay, A.; Kuznetsov, A. A.; Mazzocchi, C.; Orlin, V. N.; Pietralla, N.; Sin, M.; Spitaleri, C.; Stopani, K. A.; Tesileanu, O.; Ur, C. A.; Ursu, I.; Utsunomiya, H.; Varlamov, V. V.; Weller, H. R.; Zamfir, N. V.; Zilges, A. in The European Physical Journal A (2015). 51(12) 185.
The perspectives for photonuclear experiments at the new Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility are discussed in view of the need to accumulate novel and more precise nuclear data. The parameters of the ELI-NP gamma beam system are presented. The emerging experimental program, which will be realized at ELI-NP, is presented. Examples of day-one experiments with the nuclear resonance fluorescence technique, photonuclear reaction measurements, photofission experiments and studies of nuclear collective excitation modes and competition between various decay channels are discussed. The advantages which ELI-NP provides for all these experiments compared to the existing facilities are discussed.
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Collective excitations of 96Ru by means of (p,p′γ) experiments. Hennig, A.; Ahn, T.; Anagnostatou, V.; Blazhev, A.; Cooper, N.; Derya, V.; Elvers, M.; Endres, J.; Goddard, P.; Heinz, A.; Hughes, R. O.; Ilie, G.; Mineva, M. N.; Petkov, P.; Pickstone, S. G.; Pietralla, N.; Radeck, D.; Ross, T. J.; Savran, D.; Spieker, M.; Werner, V.; Zilges, A. in Phys. Rev. C (2015). 92(6) 064317.
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Transition probabilities in neutron-rich 84,86Se. Litzinger, J.; Blazhev, A.; Dewald, A.; Didierjean, F.; Duchêne, G.; Fransen, C.; Lozeva, R.; Sieja, K.; Verney, D.; de Angelis, G.; Bazzacco, D.; Birkenbach, B.; Bottoni, S.; Bracco, A.; Braunroth, T.; Cederwall, B.; Corradi, L.; Crespi, F. C. L.; Désesquelles, P.; Eberth, J.; Ellinger, E.; Farnea, E.; Fioretto, E.; Gernhäuser, R.; Goasduff, A.; Görgen, A.; Gottardo, A.; Grebosz, J.; Hackstein, M.; Hess, H.; Ibrahim, F.; Jolie, J.; Jungclaus, A.; Kolos, K.; Korten, W.; Leoni, S.; Lunardi, S.; Maj, A.; Menegazzo, R.; Mengoni, D.; Michelagnoli, C.; Mijatovic, T.; Million, B.; Möller, O.; Modamio, V.; Montagnoli, G.; Montanari, D.; Morales, A. I.; Napoli, D. R.; Niikura, M.; Pollarolo, G.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Rosso, D.; Sahin, E.; Salsac, M. D.; Scarlassara, F.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Theisen, Ch.; Valiente Dobón, J. J.; Vandone, V.; Vogt, A. in Phys. Rev. C (2015). 92(6) 064322.
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Production of Hyperpolarized H2 Molecules from →H Atoms in Gas-Storage Cells. Engels, R.; Gaißer, M.; Gorski, R.; Grigoryev, K.; Mikirtychyants, M.; Nass, A.; Rathmann, F.; Seyfarth, H.; Ströher, H.; Weiss, P.; Kochenda, L.; Kravtsov, P.; Trofimov, V.; Tschernov, N.; Vasilyev, A.; Vznuzdaev, M.; Schieck, H. Paetz gen. in Phys. Rev. Lett. (2015). 115(11) 113007.
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Key Nuclear Reaction Experiments Schieck, Hans Paetz gen. (2015). IOP Publishing.
In this book the author charts the developments in nuclear physics since its inception around a century ago by reviewing the key experiments that helped drive and shape our understanding of the field, especially in the context of the wider developments in physics in the early 20th century. In addition to providing a path through the field and the crucial events it looks at how these experiments not only answered key questions at the time but presented new challenges to the contemporary perception of the nuclear and sub-atomic worlds and how they helped develop our present understanding of nuclear physics.
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Origin of Low-Lying Enhanced E1 Strength in Rare-Earth Nuclei. Spieker, M.; Pascu, S.; Zilges, A.; Iachello, F. in Phys. Rev. Lett. (2015). 114(19) 192504.
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Lifetime measurement of excited low-spin states via the (p,p′γ) reaction. Hennig, A.; Derya, V.; Mineva, M.N.; Petkov, P.; Pickstone, S.G.; Spieker, M.; Zilges, A. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2015). 794 171 - 176.
Abstract In this paper a method for lifetime measurements in the sub-picosecond regime via the Doppler-shift attenuation method (DSAM) following the inelastic proton scattering reaction is presented. In a pioneering experiment we extracted the lifetimes of 30 excited low-spin states of 96Ru, taking advantage of the coincident detection of scattered protons and de-exciting γ-rays as well as the large number of particle and γ-ray detectors provided by the SONIC@HORUS setup at the University of Cologne. The large amount of new experimental data shows that this technique is suited for the measurement of lifetimes of excited low-spin states, especially for isotopes with a low isotopic abundance, where (n,n′γ) or – in case of investigating dipole excitations – (γ,γ′) experiments are not feasible due to the lack of sufficient isotopically enriched target material.
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Experimental study of the 66Ni(d,p) 67Ni one-neutron transfer reaction. Diriken, J.; Patronis, N.; Andreyev, A.; Antalic, S.; Bildstein, V.; Blazhev, A.; Darby, I. G.; De Witte, H.; Eberth, J.; Elseviers, J.; Fedosseev, V. N.; Flavigny, F.; Fransen, Ch.; Georgiev, G.; Gernhauser, R.; Hess, H.; Huyse, M.; Jolie, J.; Kröll, Th.; Krücken, R.; Lutter, R.; Marsh, B. A.; Mertzimekis, T.; Muecher, D.; Orlandi, R.; Pakou, A.; Raabe, R.; Randisi, G.; Reiter, P.; Roger, T.; Seidlitz, M.; Seliverstov, M.; Sotty, C.; Tornqvist, H.; Van De Walle, J.; Van Duppen, P.; Voulot, D.; Warr, N.; Wenander, F.; Wimmer, K. in Phys. Rev. C (2015). 91(5) 054321.
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Test of the SO(6) selection rule in 196Pt using cold-neutron capture. Jolie, J.; Régis, J.-M.; Wilmsen, D.; Saed-Samii, N.; Pfeiffer, M.; Warr, N.; Blanc, A.; Jentschel, M.; Köster, U.; Mutti, P.; Soldner, T.; Simpson, G.S.; France, G. De; Urban, W.; Drouet, F.; Vancraeyenest, A.; Bruce, A.M.; Roberts, O.J.; Fraile, L.M.; Paziy, V.; Ignatov, A.; Kröll, Th.; Ivanova, D.; Kisyov, S.; Lalkovski, S.; Podolyak, Zs.; Regan, P.H.; Wilson, E.; Korten, W.; Ur, C.A.; Lica, R.; Marginean, N. in Nuclear Physics A (2015). 934 1 - 7.
Abstract At the PF1B cold-neutron beam line of the Institut Laue Langevin, the EXILL&FATIMA array, consisting of EXOGAM Ge detectors and fast LaBr3(Ce) scintillators, was used to perform fast electronic timing measurements after the 195Pt(n, γ) reaction using a highly collimated cold-neutron beam. An upper lifetime limit was obtained for the third 0+ state in 196Pt. As this state is the lowest state of the σ=N−2 set of SO(6) states, the selection rule which forbids E2 transitions to the lower lying σ=N could be tested.
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The Cd-106(alpha, alpha)Cd-106 elastic scattering in a wide energy range for gamma process studies. Ornelas, A.; Kiss, G. G.; Mohr, P.; Galaviz, D.; Fueloep, Zs.; Gyuerky, Gy.; Mate, Z.; Rauscher, T.; Somorjai, E.; Sonnabend, K.; Zilges, A. in Nuclear Physics A (2015). 940 194-209.
Alpha elastic scattering angular distributions of the Cd-106(alpha, alpha)Cd-106 reaction were measured at three energies around the Coulomb barrier to provide a sensitive test for the alpha + nucleus optical potential parameter sets. Furthermore, the new high precision angular distributions, together with the data available from the literature were used to study the energy dependence of the locally optimized alpha + nucleus optical potential in a wide energy region ranging from E-Lab = 27.0 MeV down to 16.1 MeV. The potentials under study are a basic prerequisite for the prediction of alpha-induced reaction cross sections and thus, for the calculation of stellar reaction rates used for the astrophysical gamma process. Therefore, statistical model predictions using as input the optical potentials discussed in the present work are compared to the available Cd-106 + alpha cross section data. (C) 2015 Elsevier B.V. All rights reserved.
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A dedicated {AMS} setup for 53Mn/60Fe at the Cologne {FN} tandem accelerator. Schiffer, M.; Dewald, A.; Feuerstein, C.; Altenkirch, R.; Stolz, A.; Heinze, S. in Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms (2015). 361 95--99.
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Single-neutron orbits near 78Ni: Spectroscopy of the N=49 isotope 79Zn. Orlandi, R.; Mücher, D.; Raabe, R.; Jungclaus, A.; Pain, S.D.; Bildstein, V.; Chapman, R.; de Angelis, G.; Johansen, J.G.; Duppen, P. Van; Andreyev, A.N.; Bottoni, S.; Cocolios, T.E.; Witte, H. De; Diriken, J.; Elseviers, J.; Flavigny, F.; Gaffney, L.P.; Gernhäuser, R.; Gottardo, A.; Huyse, M.; Illana, A.; Konki, J.; Kröll, T.; Krücken, R.; Lane, J.F.W.; Liberati, V.; Marsh, B.; Nowak, K.; Nowacki, F.; Pakarinen, J.; Rapisarda, E.; Recchia, F.; Reiter, P.; Roger, T.; Sahin, E.; Seidlitz, M.; Sieja, K.; Smith, J.F.; Dobón, J.J. Valiente; von Schmid, M.; Voulot, D.; Warr, N.; Wenander, F.K.; Wimmer, K. in Physics Letters B (2015). 740 298 - 302.
Abstract Single-neutron states in the Z=30, N=49 isotope 79Zn have been populated using the 78Zn(d, p)79Zn transfer reaction at REX-ISOLDE, CERN. The experimental setup allowed the combined detection of protons ejected in the reaction, and of γ rays emitted by 79Zn. The analysis reveals that the lowest excited states populated in the reaction lie at approximately 1 MeV of excitation, and involve neutron orbits above the N=50 shell gap. From the analysis of γ-ray data and of proton angular distributions, characteristic of the amount of angular momentum transferred, a 5/2+ configuration was assigned to a state at 983 keV. Comparison with large-scale-shell-model calculations supports a robust neutron N=50 shell-closure for 78Ni. These data constitute an important step towards the understanding of the magicity of 78Ni and of the structure of nuclei in the region.
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Testing refined shell-model interactions in the sd shell: Coulomb excitation of 26Na. Siebeck, B.; Seidlitz, M.; Blazhev, A.; Reiter, P.; Altenkirch, R.; Bauer, C.; Butler, P. A.; De Witte, H.; Elseviers, J.; Gaffney, L. P.; Hess, H.; Huyse, M.; Kröll, T.; Lutter, R.; Pakarinen, J.; Pietralla, N.; Radeck, F.; Scheck, M.; Schneiders, D.; Sotty, C.; Van Duppen, P.; Vermeulen, M.; Voulot, D.; Warr, N.; Wenander, F. in Phys. Rev. C (2015). 91(1) 014311.
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Collectivity in the light radon nuclei measured directly via Coulomb excitation. Gaffney, L. P.; Robinson, A. P.; Jenkins, D. G.; Andreyev, A. N.; Bender, M.; Blazhev, A.; Bree, N.; Bruyneel, B.; Butler, P. A.; Cocolios, T. E.; Davinson, T.; Deacon, A. N.; De Witte, H.; DiJulio, D.; Diriken, J.; Ekström, A.; Fransen, Ch.; Freeman, S. J.; Geibel, K.; Grahn, T.; Hadinia, B.; Hass, M.; Heenen, P.-H.; Hess, H.; Huyse, M.; Jakobsson, U.; Kesteloot, N.; Konki, J.; Kröll, Th.; Kumar, V.; Ivanov, O.; Martin-Haugh, S.; Mücher, D.; Orlandi, R.; Pakarinen, J.; Petts, A.; Peura, P.; Rahkila, P.; Reiter, P.; Scheck, M.; Seidlitz, M.; Singh, K.; Smith, J. F.; Van de Walle, J.; Van Duppen, P.; Voulot, D.; Wadsworth, R.; Warr, N.; Wenander, F.; Wimmer, K.; Wrzosek-Lipska, K.; Zielińska, M. in Phys. Rev. C (2015). 91(6) 064313.
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Shell evolution beyond N=40: 69,71,73Cu. Sahin, E.; Doncel, M.; Sieja, K.; de Angelis, G.; Gadea, A.; Quintana, B.; Görgen, A.; Modamio, V.; Mengoni, D.; Valiente-Dobón, J. J.; John, P. R.; Albers, M.; Bazzacco, D.; Benzoni, G.; Birkenbach, B.; Cederwall, B.; Clément, E.; Curien, D.; Corradi, L.; Désesquelles, P.; Dewald, A.; Didierjean, F.; Duchêne, G.; Eberth, J.; Erduran, M. N.; Farnea, E.; Fioretto, E.; de France, G.; Fransen, C.; Gernhäuser, R.; Gottardo, A.; Hackstein, M.; Hagen, T.; Hernández-Prieto, A.; Hess, H.; Hüyük, T.; Jungclaus, A.; Klupp, S.; Korten, W.; Kusoglu, A.; Lenzi, S. M.; Ljungvall, J.; Louchart, C.; Lunardi, S.; Menegazzo, R.; Michelagnoli, C.; Mijatović, T.; Million, B.; Molini, P.; Montagnoli, G.; Montanari, D.; Möller, O.; Napoli, D. R.; Obertelli, A.; Orlandi, R.; Pollarolo, G.; Pullia, A.; Recchia, F.; Reiter, P.; Rosso, D.; Rother, W.; Salsac, M.-D.; Scarlassara, F.; Schlarb, M.; Siem, S.; Singh, Pushpendra P.; Söderström, P.-A.; Stefanini, A. M.; Stézowski, O.; Sulignano, B.; Szilner, S.; Theisen, Ch.; Ur, C. A.; Yalcinkaya, M. in Phys. Rev. C (2015). 91(3) 034302.
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1− and 2+ discrete states in 90Zr populated via the (17O,17O′γ) reaction. Crespi, F. C. L.; Bracco, A.; Nicolini, R.; Lanza, E. G.; Vitturi, A.; Mengoni, D.; Leoni, S.; Benzoni, G.; Blasi, N.; Boiano, C.; Bottoni, S.; Brambilla, S.; Camera, F.; Corsi, A.; Giaz, A.; Million, B.; Pellegri, L.; Vandone, V.; Wieland, O.; Bednarczyk, P.; Ciemała, M.; Kmiecik, M.; Krzysiek, M.; Maj, A.; Bazzacco, D.; Bellato, M.; Birkenbach, B.; Bortolato, D.; Calore, E.; Cederwall, B.; de Angelis, G.; Désesquelles, P.; Eberth, J.; Farnea, E.; Gadea, A.; Görgen, A.; Gottardo, A.; Hess, H.; Isocrate, R.; Jolie, J.; Jungclaus, A.; Kempley, R. S.; Labiche, M.; Menegazzo, R.; Michelagnoli, C.; Molini, P.; Napoli, D. R.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Sahin, E.; Siem, S.; Söderström, P.-A.; Stezowski, O.; Theisen, Ch.; Ur, C.; Valiente-Dobón, J. J. in Phys. Rev. C (2015). 91(2) 024323.
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Total and partial cross sections of the 112Sn(α,γ)116Te reaction measured via in-beam γ-ray spectroscopy. Netterdon, L.; Mayer, J.; Scholz, P.; Zilges, A. in Phys. Rev. C (2015). 91(3) 035801.
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Detailed spectroscopy of quadrupole and octupole states in 168Yb. Pascu, S.; Bucurescu, D.; Căta-Danil, Gh.; Derya, V.; Elvers, M.; Filipescu, D.; Ghiţă, D. G.; Glodariu, T.; Hennig, A.; Mihai, C.; Mărginean, N.; Mărginean, R.; Negret, A.; Netterdon, L.; Pickstone, S. G.; Sava, T.; Spieker, M.; Stroe, L.; Zamfir, N. V.; Zilges, A. in Phys. Rev. C (2015). 91(3) 034321.
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Lifetime measurement of excited low-spin states via the (p, p `gamma) reaction. Hennig, A.; Derya, V.; Mineva, M. N.; Petkov, P.; Pickstone, S. G.; Spieker, M.; Zilges, A. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2015). 794 171-176.
In this paper a method for lifetime measurements in the sub picosecond regime via the Doppler-shift attenuation method (DSAM) following the inelastic proton scattering reaction is presented. In a pioneering experiment we extracted the lifetimes of 30 excited low spin states of Ru-96, taking advantage of the coincident detection of scattered protons and de exciting gamma-rays as well as the large number of particle and gamma-ray detectors provided by the SONICCDHORUS setup at the University of Cologne. The large amount of new experimental data shows that this technique is suited for the measurement of lifetimes of excited low spin slates, especially for isotopes with a low isotopic abundance, where (n,n'gamma) or - in case of investigating dipole excitations - (gamma, gamma') experiments are not feasible due to the lack of sufficient isotopically enriched target material. (C) 2015 Elsevier B.V. All rights reserved.
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Experimental constraints on the γ-ray strength function in 90Zr using partial cross sections of the Y89(p,γ)Zr90 reaction. Netterdon, L.; Endres, A.; Goriely, S.; Mayer, J.; Scholz, P.; Spieker, M.; Zilges, A. in Physics Letters B (2015). 744 358 - 362.
Abstract Partial cross sections of the Y89(p,γ)Zr90 reaction have been measured to investigate the γ-ray strength function in the neutron–magic nucleus 90Zr. For five proton energies between Ep=3.65 MeV and Ep=4.70 MeV, partial cross sections for the population of seven discrete states in 90Zr have been determined by means of in-beam γ-ray spectroscopy. Since these γ-ray transitions are dominantly of E1 character, the present measurement allows an access to the low-lying dipole strength in 90Zr. A γ-ray strength function based on the experimental data could be extracted, which is used to describe the total and partial cross sections of this reaction by Hauser–Feshbach calculations successfully. Significant differences with respect to previously measured strength functions from photoabsorption data point towards deviations from the Brink–Axel hypothesis relating the photo-excitation and de-excitation strength functions.
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Cluster-transfer reactions with radioactive beams: A spectroscopic tool for neutron-rich nuclei. Bottoni, S.; Leoni, S.; Fornal, B.; Raabe, R.; Rusek, K.; Benzoni, G.; Bracco, A.; Crespi, F. C. L.; Morales, A. I.; Bednarczyk, P.; Cieplicka-Oryńczak, N.; Królas, W.; Maj, A.; Szpak, B.; Callens, M.; Bouma, J.; Elseviers, J.; De Witte, H.; Flavigny, F.; Orlandi, R.; Reiter, P.; Seidlitz, M.; Warr, N.; Siebeck, B.; Hellgartner, S.; Mücher, D.; Pakarinen, J.; Vermeulen, M.; Bauer, C.; Georgiev, G.; Janssens, R. V. F.; Balabanski, D.; Sferrazza, M.; Kowalska, M.; Rapisarda, E.; Voulot, D.; Lozano Benito, M.; Wenander, F. in Phys. Rev. C (2015). 92(2) 024322.
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The γ-ray spectrometer HORUS and its applications for nuclear astrophysics. Netterdon, L.; Derya, V.; Endres, J.; Fransen, C.; Hennig, A.; Mayer, J.; Müller-Gatermann, C.; Sauerwein, A.; Scholz, P.; Spieker, M.; Zilges, A. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2014). 754 94 - 100.
Abstract A dedicated setup for the in-beam measurement of absolute cross-sections of astrophysically relevant charged-particle induced reactions is presented. These, usually very low, cross-sections at energies of astrophysical interest are important to improve the modeling of the nucleosynthesis processes of heavy nuclei. Particular emphasis is put on the production of the p nuclei during the astrophysical γ process. The recently developed setup utilizes the high-efficiency γ-ray spectrometer HORUS, which is located at the 10MV FN tandem ion accelerator of the Institute for Nuclear Physics in Cologne. The design of this setup will be presented and results of the recently measured 89Y(p,γ)90Zr reaction will be discussed. The excellent agreement with existing data shows that the HORUS spectrometer is a powerful tool to determine total and partial cross-sections using the in-beam method with high-purity germanium detectors.
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Measurement of the 187Re(α,n)190Ir reaction cross section at sub-Coulomb energies using the Cologne Clover Counting Setup. Scholz, P.; Endres, A.; Hennig, A.; Netterdon, L.; Becker, H. W.; Endres, J.; Mayer, J.; Giesen, U.; Rogalla, D.; Schlüter, F.; Pickstone, S. G.; Zell, K. O.; Zilges, A. in Phys. Rev. C (2014). 90(6) 065807.
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B-13,B-14(n,gamma) via Coulomb Dissociation for Nucleosynthesis towards the r-Process. Altstadt, S. G.; Adachi, T.; Aksyutina, Y.; Alcantara, J.; Alvarez-Pol, H.; Ashwood, N.; Atar, L.; Aumann, T.; Avdeichikov, V.; Barr, M.; Beceiro, S.; Bemmerer, D.; Benlliure, J.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Burgunder, G.; Caamano, M.; Caesar, C.; Casarejos, E.; Catford, W.; Cederkall, J.; Chakraborty, S.; Chartier, M.; Chulkov, L.; Cortina-Gil, D.; Pramanik, U. Datta; Fernandez, P. Diaz; Dillmann, I.; Elekes, Z.; Enders, J.; Ershova, O.; Estrade, A.; Farinon, F.; Fraile, L. M.; Freer, M.; Freudenberger, M.; Fynbo, H. O. U.; Galaviz, D.; Geissel, H.; Gernhaeuser, R.; Goebel, K.; Golubev, P.; Gonzalez Diaz, D.; Hagdahl, J.; Heftrich, T.; Heil, M.; Heine, M.; Heinz, A.; Henriques, A.; Holl, M.; Holt, J. D.; Ickert, G.; Ignatov, A.; Jakobsson, B.; Johansson, H. T.; Jonson, B.; Kalantar-Nayestanaki, N.; Kanungo, R.; Kelic-Heil, A.; Knoebel, R.; Kroell, T.; Kruecken, R.; Kurcewicz, J.; Kurz, N.; Labiche, M.; Langer, C.; Le Bleis, T.; Lemmon, R.; Lepyoshkina, O.; Machado, J.; Marganiec, J.; Maroussov, V.; Menendez, J.; Mostazo, M.; Movsesyan, A.; Najafi, M. A.; Nilsson, T.; Nociforo, C.; Panin, V.; Perea, A.; Pietri, S.; Plag, R.; Prochazka, A.; Rahaman, A.; Rastrepina, G.; Reifarth, R.; Ribeiro, G.; Ricciardi, M. V.; Rigollet, C.; Riisager, K.; Roeder, M.; Rossi, D.; Sanchez del Rio, J.; Savran, D.; Scheit, H.; Schwenk, A.; Simon, H.; Simonis, J.; Sonnabend, K.; Sorlin, O.; Stoica, V.; Streicher, B.; Taylor, J.; Tengblad, O.; Terashima, S.; Thies, R.; Togano, Y.; Uberseder, E.; Van de Walle, J.; Velho, P.; Volkov, V.; Wagner, A.; Wamers, F.; Weick, H.; Weigand, M.; Wheldon, C.; Wilson, G.; Wimmer, C.; Winfield, J. S.; Woods, P.; Yakorev, D.; Zhukov, M. V.; Zilges, A.; Zoric, M.; Zuber, K.; Collaboration, R3B in NUCLEAR DATA SHEETS (2014). 120(SI) 197-200.
Radioactive beams of B-14,B-15 produced by fragmentation of a primary Ar-40 beam were directed onto a Pb target to investigate the neutron breakup within the Coulomb field. The experiment was performed at the LAND/(RB)-B-3 setup. Preliminary results for the Coulomb dissociation cross sections as well as for the astrophysically interesting inverse reactions, B-13,B-14(n,gamma), are presented.
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The structure of ¹⁹³Au within the Interacting Boson Fermion Model. Thomas, T.; Bernards, C.; Régis, J.-M.; Albers, M.; Fransen, C.; Jolie, J.; Heinze, S.; Radeck, D.; Warr, N.; Zell, K.-O. in Nuclear Physics A (2014). 922 200 - 224.
Abstract A γγ angular correlation experiment investigating the nucleus 193Au is presented. In this work the level scheme of 193Au is extended by new level information on spins, multipolarities and newly observed states. The new results are compared with theoretical predictions from a general Interacting Boson Fermion Model (IBFM) calculation for the positive-parity states. The experimental data is in good agreement with an IBFM calculation using all proton orbitals between the shell closures at Z=50 and Z=126. As a dominant contribution of the d3/2 orbital to the wave function of the lowest excited states is observed, a truncated model of the IBFM using a Bose–Fermi symmetry is applied to the describe 193Au. Using the parameters of a fit performed for 193Au, the level scheme of 192Pt, the supersymmetric partner of 193Au, is predicted but shows a too small boson seniority splitting. We obtained a common fit by including states observed in 192Pt. With the new parameters a supersymmetric description of both nuclei is established.
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Coulomb excitation of 29,30Na: Mapping the borders of the island of inversion. Seidlitz, M.; Reiter, P.; Altenkirch, R.; Bastin, B.; Bauer, C.; Blazhev, A.; Bree, N.; Bruyneel, B.; Butler, P. A.; Cederkäll, J.; Davinson, T.; De Witte, H.; DiJulio, D. D.; Diriken, J.; Gaffney, L. P.; Geibel, K.; Georgiev, G.; Gernhäuser, R.; Huyse, M.; Kesteloot, N.; Kröll, T.; Krücken, R.; Lutter, R.; Pakarinen, J.; Radeck, F.; Scheck, M.; Schneiders, D.; Siebeck, B.; Sotty, C.; Steinbach, T.; Taprogge, J.; Van Duppen, P.; Van de Walle, J.; Voulot, D.; Warr, N.; Wenander, F.; Wimmer, K.; Woods, P. J.; Wrzosek-Lipska, K. in Phys. Rev. C (2014). 89(2) 024309.
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Isospin properties of electric dipole excitations in ⁴⁸Ca. Derya, V.; Savran, D.; Endres, J.; Harakeh, M.N.; Hergert, H.; Kelley, J.H.; Papakonstantinou, P.; Pietralla, N.; Ponomarev, V.Yu.; Roth, R.; Rusev, G.; Tonchev, A.P.; Tornow, W.; Wörtche, H.J.; Zilges, A. in Physics Letters B (2014). 730 288 - 292.
Abstract Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus 48Ca below the neutron threshold. Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and nearly mono-energetic linearly polarized photons with energies between 6.6 and 9.51 MeV provided strength distribution and parities, and an (α,α′γ) experiment at Eα=136MeV gave cross sections for an isoscalar probe. The unexpected difference observed in the dipole response is compared to calculations using the first-order random-phase approximation and points to an energy-dependent isospin character. A strong isoscalar state at 7.6 MeV was identified for the first time supporting a recent theoretical prediction.
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Coulomb excitation of neutron-rich Cd isotopes. Ilieva, S.; Thürauf, M.; Kröll, Th.; Krücken, R.; Behrens, T.; Bildstein, V.; Blazhev, A.; Bönig, S.; Butler, P. A.; Cederkäll, J.; Davinson, T.; Delahaye, P.; Diriken, J.; Ekström, A.; Finke, F.; Fraile, L. M.; Franchoo, S.; Fransen, Ch.; Georgiev, G.; Gernhäuser, R.; Habs, D.; Hess, H.; Hurst, A. M.; Huyse, M.; Ivanov, O.; Iwanicki, J.; Kent, P.; Kester, O.; Köster, U.; Lutter, R.; Mahgoub, M.; Martin, D.; Mayet, P.; Maierbeck, P.; Morgan, T.; Niedermeier, O.; Pantea, M.; Reiter, P.; Rodrìguez, T. R.; Rolke, Th.; Scheit, H.; Scherillo, A.; Schwalm, D.; Seidlitz, M.; Sieber, T.; Simpson, G. S.; Stefanescu, I.; Thiel, S.; Thirolf, P. G.; Van de Walle, J.; Van Duppen, P.; Voulot, D.; Warr, N.; Weinzierl, W.; Weisshaar, D.; Wenander, F.; Wiens, A.; Winkler, S. in Phys. Rev. C (2014). 89(1) 014313.
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Shape Coexistence in the Neutron-Deficient Even-Even ¹⁸²⁻¹⁸⁸Hg Isotopes Studied via Coulomb Excitation. Bree, N.; Wrzosek-Lipska, K.; Petts, A.; Andreyev, A.; Bastin, B.; Bender, M.; Blazhev, A.; Bruyneel, B.; Butler, P. A.; Butterworth, J.; Carpenter, M. P.; Cederkäll, J.; Clément, E.; Cocolios, T. E.; Deacon, A.; Diriken, J.; Ekström, A.; Fitzpatrick, C.; Fraile, L. M.; Fransen, Ch.; Freeman, S. J.; Gaffney, L. P.; García-Ramos, J. E.; Geibel, K.; Gernhäuser, R.; Grahn, T.; Guttormsen, M.; Hadinia, B.; Hadyńska-Kle¸k, K.; Hass, M.; Heenen, P.-H.; Herzberg, R.-D.; Hess, H.; Heyde, K.; Huyse, M.; Ivanov, O.; Jenkins, D. G.; Julin, R.; Kesteloot, N.; Kröll, Th.; Krücken, R.; Larsen, A. C.; Lutter, R.; Marley, P.; Napiorkowski, P. J.; Orlandi, R.; Page, R. D.; Pakarinen, J.; Patronis, N.; Peura, P. J.; Piselli, E.; Rahkila, P.; Rapisarda, E.; Reiter, P.; Robinson, A. P.; Scheck, M.; Siem, S.; Singh Chakkal, K.; Smith, J. F.; Srebrny, J.; Stefanescu, I.; Tveten, G. M.; Van Duppen, P.; Van de Walle, J.; Voulot, D.; Warr, N.; Wenander, F.; Wiens, A.; Wood, J. L.; Zielińska, M. in Phys. Rev. Lett. (2014). 112(16) 162701.
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Nuclear Reactions - An Introduction Paetz gen. Schieck, Hans in Lecture Notes in Physics (2014). Springer.
Nuclei and nuclear reactions offer a unique setting for investigating three (and in some cases even all four) of the fundamental forces in nature. Nuclei have been shown – mainly by performing scattering experiments with electrons, muons and neutrinos – to be extended objects with complex internal structures: constituent quarks; gluons, whose exchange binds the quarks together; sea-quarks, the ubiquitous virtual quark-antiquark pairs and last but not least, clouds of virtual mesons, surrounding an inner nuclear region, their exchange being the source of the nucleon-nucleon interaction. The interplay between the (mostly attractive) hadronic nucleon-nucleon interaction and the repulsive Coulomb force is responsible for the existence of nuclei; their degree of stability, expressed in the details and limits of the chart of nuclides; their rich structure and the variety of their interactions. Despite the impressive successes of the classical nuclear models and of ab-initio approaches, there is clearly no end in sight for either theoretical or experimental developments as shown e.g. by the recent need to introduce more sophisticated three-body interactions to account for an improved picture of nuclear structure and reactions. Yet, it turns out that the internal structure of the nucleons has comparatively little influence on the behavior of the nucleons in nuclei and nuclear physics – especially nuclear structure and reactions – is thus a field of science in its own right, without much recourse to subnuclear degrees of freedom. This book collects essential material that was presented in the form of lectures notes in nuclear physics courses for graduate students at the University of Cologne. It follows the course's approach, conveying the subject matter by combining experimental facts and experimental methods and tools with basic theoretical knowledge. Emphasis is placed on the importance of spin and orbital angular momentum (leading e.g. to applications in energy research, such as fusion with polarized nuclei) and on the operational definition of observables in nuclear physics. The end-of-chapter problems serve above all to elucidate and detail physical ideas that could not be presented in full detail in the main text. Readers are assumed to have a working knowledge of quantum mechanics and a basic grasp of both non-relativistic and relativistic kinematics; the latter in particular is a prerequisite for interpreting nuclear reactions and the connections to particle and high-energy physics.
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Isospin properties of electric dipole excitations in Ca-48. Derya, V.; Savran, D.; Endres, J.; Harakeh, M. N.; Hergert, H.; Kelley, J. H.; Papakonstantinou, P.; Pietralla, N.; Ponomarev, V. Yu.; Roth, R.; Rusev, G.; Tonchev, A. P.; Tornow, W.; Wortche, H. J.; Zilges, A. in Physics Letters B (2014). 730 288-292.
Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus Ca-48 below the neutron threshold. Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and nearly mono-energetic linearly polarized photons with energies between 6.6 and 9.51 MeV provided strength distribution and parities, and an (alpha, alpha'gamma) experiment at E-alpha = 136 MeV gave cross sections for an isoscalar probe. The unexpected difference observed in the dipole response is compared to calculations using the first-order random-phase approximation and points to an energy-dependent isospiu character. A strong isoscalar state at 7.6 MeV was identified for the first time supporting a recent theoretical prediction. (C) 2014 The Authors. Published by Elsevier B.V.
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Measurement of the Re-187(alpha, n)Ir-190 reaction cross section at sub-Coulomb energies using the Cologne Clover Counting Setup. Scholz, P.; Endres, A.; Hennig, A.; Netterdon, L.; Becker, H. W.; Endres, J.; Mayer, J.; Giesen, U.; Rogalla, D.; Schlueter, F.; Pickstone, S. G.; Zell, K. O.; Zilges, A. in Phys. Rev. C (2014). 90(6)
Background: Uncertainties in adopted models of particle + nucleus optical-model potentials directly influence the accuracy in the theoretical predictions of reaction rates as they are needed for reaction-network calculations in, for instance, gamma-process nucleosynthesis. The improvement of the alpha + nucleus optical-model potential is hampered by the lack of experimental data at astrophysically relevant energies especially for heavier nuclei. Purpose: Measuring the Re-187(alpha,n)Ir-190 reaction cross section at sub-Coulomb energies extends the scarce experimental data available in this mass region and helps understanding the energy dependence of the imaginary part of the alpha + nucleus optical-model potential at low energies. Method: Applying the activation method, after the irradiation of natural rhenium targets with alpha-particle energies of 12.4 to 14.1 MeV, the reaction yield and thus the reaction cross section were determined via gamma-ray spectroscopy by using the Cologne Clover Counting Setup and the method of gamma gamma coincidences. Results: Cross-section values at five energies close to the astrophysically relevant energy region were measured. Statistical model calculations revealed discrepancies between the experimental values and predictions based on widely used alpha+nucleus optical-model potentials. However, an excellent reproduction of the measured cros-ssection values could be achieved from calculations based on the so-called Sauerwein-Rauscher alpha + nucleus optical-model potential. Conclusion: The results obtained indicate that the energy dependence of the imaginary part of the alpha + nucleus optical-model potential can be described by an exponential decrease. Successful reproductions of measured cross sections at low energies for alpha-induced reactions in the mass range 141 <= A <= 187 confirm the global character of the Sauerwein-Rauscher potential.
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Mixed-symmetry octupole and hexadecapole excitations in the N=52 isotones. Hennig, A.; Spieker, M.; Werner, V.; Ahn, T.; Anagnostatou, V.; Cooper, N.; Derya, V.; Elvers, M.; Endres, J.; Goddard, P.; Heinz, A.; Hughes, R. O.; Ilie, G.; Mineva, M. N.; Petkov, P.; Pickstone, S. G.; Pietralla, N.; Radeck, D.; Ross, T. J.; Savran, D.; Zilges, A. in Phys. Rev. C (2014). 90(5) 051302.
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Fission Barrier of Superheavy Nuclei and Persistence of Shell Effects at High Spin: Cases of 254No and 220Th. Henning, Greg; Khoo, T. L.; Lopez-Martens, A.; Seweryniak, D.; Alcorta, M.; Asai, M.; Back, B. B.; Bertone, P. F.; Boilley, D.; Carpenter, M. P.; Chiara, C. J.; Chowdhury, P.; Gall, B.; Greenlees, P. T.; Gürdal, G.; Hauschild, K.; Heinz, A.; Hoffman, C. R.; Janssens, R. V. F.; Karpov, A. V.; Kay, B. P.; Kondev, F. G.; Lakshmi, S.; Lauritsen, T.; Lister, C. J.; McCutchan, E. A.; Nair, C.; Piot, J.; Potterveld, D.; Reiter, P.; Rogers, A. M.; Rowley, N.; Zhu, S. in Phys. Rev. Lett. (2014). 113(26) 262505.
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Bose–Fermi symmetry in the odd–even gold isotopes. Thomas, T.; Régis, J.-M.; Jolie, J.; Heinze, S.; Albers, M.; Bernards, C.; Fransen, C.; Radeck, D. in Nuclear Physics A (2014). 925 96 - 111.
Abstract In this work the results of an in-beam experiment on 195Au are presented, yielding new spins, multipole mixing ratios, and new low-lying states essential for the understanding of this nucleus. The positive-parity states from this work together with compiled data from the available literature for 185–199Au are compared to Interacting Boson Fermion Model calculations employing the Spin(6) Bose–Fermi symmetry. The evolution of the parameters for the τ splitting and the J splitting reveals a smooth behavior. Thereby, a common description based on the Bose–Fermi symmetry is found for 189–199Au. Furthermore, the calculated E2 transition strengths are compared to experimental values with fixed effective boson and fermion charges for all odd–even gold isotopes, emphasizing that the Spin(6) Bose–Fermi symmetry is valid for the gold isotopes.
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Low-velocity transient-field technique with radioactive ion beams: g factor of the first excited 2⁺ state in ⁷²Zn. Illana, A.; Jungclaus, A.; Orlandi, R.; Perea, A.; Bauer, C.; Briz, J. A.; Egido, J. L.; Gernhäuser, R.; Leske, J.; Mücher, D.; Pakarinen, J.; Pietralla, N.; Rajabali, M.; Rodríguez, T. R.; Seiler, D.; Stahl, C.; Voulot, D.; Wenander, F.; Blazhev, A.; De Witte, H.; Reiter, P.; Seidlitz, M.; Siebeck, B.; Vermeulen, M. J.; Warr, N. in Phys. Rev. C (2014). 89(5) 054316.
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Isospin symmetry in the sd shell: Transition strengths in the neutron-deficient sd shell nucleus ³³Ar. Wendt, A.; Taprogge, J.; Reiter, P.; Golubev, P.; Grawe, H.; Pietri, S.; Boutachkov, P.; Algora, A.; Ameil, F.; Bentley, M. A.; Blazhev, A.; Bloor, D.; Nara Singh, B. S.; Bowry, M.; Bracco, A.; Braun, N.; Camera, F.; Cederkäll, J.; Crespi, F.; de la Salle, A.; DiJulio, D.; Doornenbal, P.; Geibel, K.; Gellanki, J.; Gerl, J.; Grȩbosz, J.; Guastalla, G.; Habermann, T.; Hackstein, M.; Hoischen, R.; Jungclaus, A.; Merchán, E.; Million, B.; Morales, A.; Moschner, K.; Podolyák, Zs.; Pietralla, N.; Ralet, D.; Reese, M.; Rudolph, D.; Scruton, L.; Siebeck, B.; Warr, N.; Wieland, O.; Wollersheim, H. J. in Phys. Rev. C (2014). 90(5) 054301.
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Pygmy dipole resonance in ¹²⁴Sn populated by inelastic scattering of ¹⁷O. Pellegri, L.; Bracco, A.; Crespi, F.C.L.; Leoni, S.; Camera, F.; Lanza, E.G.; Kmiecik, M.; Maj, A.; Avigo, R.; Benzoni, G.; Blasi, N.; Boiano, C.; Bottoni, S.; Brambilla, S.; Ceruti, S.; Giaz, A.; Million, B.; Morales, A.I.; Nicolini, R.; Vandone, V.; Wieland, O.; Bazzacco, D.; Bednarczyk, P.; Bellato, M.; Birkenbach, B.; Bortolato, D.; Cederwall, B.; Charles, L.; Ciemala, M.; Angelis, G. De; Désesquelles, P.; Eberth, J.; Farnea, E.; Gadea, A.; Gernhäuser, R.; Görgen, A.; Gottardo, A.; Grebosz, J.; Hess, H.; Isocrate, R.; Jolie, J.; Judson, D.; Jungclaus, A.; Karkour, N.; Krzysiek, M.; Litvinova, E.; Lunardi, S.; Mazurek, K.; Mengoni, D.; Michelagnoli, C.; Menegazzo, R.; Molini, P.; Napoli, D.R.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Salsac, M.D.; Siebeck, B.; Siem, S.; Simpson, J.; Söderström, P.-A.; Stezowski, O.; Theisen, Ch.; Ur, C.; Dobon, J.J. Valiente; Zieblinski, M. in Physics Letters B (2014). 738 519 - 523.
Abstract The γ decay from the high-lying states of 124Sn was measured using the inelastic scattering of 17O at 340 MeV. The emitted γ rays were detected with high resolution with the AGATA demonstrator array and the scattered ions were detected in two segmented ΔE–E silicon telescopes. The angular distribution was measured both for the γ rays and the scattered 17O ions. An accumulation of E1 strength below the particle threshold was found and compared with previous data obtained with (γ,γ′) and (α,α′γ) reactions. The present results of elastic scattering, and excitation of E2 and E1 states were analysed using the DWBA approach. From this comprehensive description the isoscalar component of the 1− excited states was extracted. The obtained values are based on the comparison of the data with DWBA calculations including a form factor deduced using a microscopic transition density.
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Study of the deformation-driving νd5/2 orbital in 6728Ni39 using one-neutron transfer reactions. Diriken, J.; Patronis, N.; Andreyev, A.N.; Antalic, S.; Bildstein, V.; Blazhev, A.; Darby, I.G.; Witte, H. De; Eberth, J.; Elseviers, J.; Fedosseev, V.N.; Flavigny, F.; Fransen, Ch.; Georgiev, G.; Gernhauser, R.; Hess, H.; Huyse, M.; Jolie, J.; Kröll, Th.; Krücken, R.; Lutter, R.; Marsh, B.A.; Mertzimekis, T.; Muecher, D.; Nowacki, F.; Orlandi, R.; Pakou, A.; Raabe, R.; Randisi, G.; Reiter, P.; Roger, T.; Seidlitz, M.; Seliverstov, M.; Sieja, K.; Sotty, C.; Tornqvist, H.; Walle, J. Van De; Duppen, P. Van; Voulot, D.; Warr, N.; Wenander, F.; Wimmer, K. in Physics Letters B (2014). 736 533 - 538.
Abstract The νg9/2,d5/2,s1/2 orbitals are assumed to be responsible for the swift onset of collectivity observed in the region below 68Ni. Especially the single-particle energies and strengths of these orbitals are of importance. We studied such properties in the nearby 67Ni nucleus, by performing a (d,p)-experiment in inverse kinematics employing a post-accelerated radioactive ion beam (RIB) at the REX-ISOLDE facility. The experiment was performed at an energy of 2.95 MeV/u using a combination of the T-REX particle detectors, the Miniball γ-detection array and a newly-developed delayed-correlation technique as to investigate μs-isomers. Angular distributions of the ground state and multiple excited states in 67Ni were obtained and compared with DWBA cross-section calculations, leading to the identification of positive-parity states with substantial νg9/2 (1007 keV) and νd5/2 (2207 keV and 3277 keV) single-particle strengths up to an excitation energy of 5.8 MeV. 50% of the νd5/2 single-particle strength relative to the νg9/2-orbital is concentrated in and shared between the first two observed 5/2+ levels. A comparison with extended Shell Model calculations and equivalent (3He, d) studies in the region around 9040Zr50 highlights similarities for the strength of the negative-parity pf and positive-parity g9/2 state, but differences are observed for the d5/2 single-particle strength.
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Cross-section measurement of the 130Ba(p,γ)131La reaction for γ-process nucleosynthesis. Netterdon, L.; Endres, A.; Kiss, G. G.; Mayer, J.; Rauscher, T.; Scholz, P.; Sonnabend, K.; Török, Zs.; Zilges, A. in Phys. Rev. C (2014). 90(3) 035806.
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Shape evolution in the neutron-rich osmium isotopes: Prompt γ-ray spectroscopy of 196Os. John, P. R.; Modamio, V.; Valiente-Dobón, J. J.; Mengoni, D.; Lunardi, S.; Rodríguez, T. R.; Bazzacco, D.; Gadea, A.; Wheldon, C.; Alexander, T.; de Angelis, G.; Ashwood, N.; Barr, M.; Benzoni, G.; Birkenbach, B.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; Bottoni, S.; Bowry, M.; Bracco, A.; Browne, F.; Bunce, M.; Camera, F.; Cederwall, B.; Corradi, L.; Crespi, F. C. L.; Désesquelles, P.; Eberth, J.; Farnea, E.; Fioretto, E.; Görgen, A.; Gottardo, A.; Grebosz, J.; Grente, L.; Hess, H.; Jungclaus, A.; Kokalova, Tz.; Korichi, A.; Korten, W.; Kuşoğlu, A.; Lenzi, S.; Leoni, S.; Ljungvall, J.; Maron, G.; Meczynski, W.; Melon, B.; Menegazzo, R.; Michelagnoli, C.; Mijatović, T.; Million, B.; Molini, P.; Montagnoli, G.; Montanari, D.; Napoli, D. R.; Nolan, P.; Oziol, Ch.; Podolyák, Zs.; Pollarolo, G.; Pullia, A.; Quintana, B.; Recchia, F.; Reiter, P.; Roberts, O. J.; Rosso, D.; Şahin, E.; Salsac, M.-D.; Scarlassara, F.; Sferrazza, M.; Simpson, J.; Söderström, P.-A.; Stefanini, A. M.; Stezowski, O.; Szilner, S.; Theisen, Ch.; Ur, C. A.; Walshe, J. in Phys. Rev. C (2014). 90(2) 021301.
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Low-lying isomeric states in 80Ga from the β- decay of 80Zn. Lică, R.; Mărginean, N.; Ghiţă, D. G.; Mach, H.; Fraile, L. M.; Simpson, G. S.; Aprahamian, A.; Bernards, C.; Briz, J. A.; Bucher, B.; Chiara, C. J.; Dlouhý, Z.; Gheorghe, I.; Hoff, P.; Jolie, J.; Köster, U.; Kurcewicz, W.; Mărginean, R.; Olaizola, B.; Paziy, V.; Régis, J. M.; Rudigier, M.; Sava, T.; Stănoiu, M.; Stroe, L.; Walters, W. B. in Phys. Rev. C (2014). 90(1) 014320.
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B(E2;2₁⁺→0₁⁺) value in 90Kr. Régis, J.-M.; Jolie, J.; Saed-Samii, N.; Warr, N.; Pfeiffer, M.; Blanc, A.; Jentschel, M.; Köster, U.; Mutti, P.; Soldner, T.; Simpson, G. S.; Drouet, F.; Vancraeyenest, A.; de France, G.; Clément, E.; Stezowski, O.; Ur, C. A.; Urban, W.; Regan, P. H.; Podolyák, Zs.; Larijani, C.; Townsley, C.; Carroll, R.; Wilson, E.; Fraile, L. M.; Mach, H.; Paziy, V.; Olaizola, B.; Vedia, V.; Bruce, A. M.; Roberts, O. J.; Smith, J. F.; Kröll, T.; Hartig, A.-L.; Ignatov, A.; Ilieva, S.; Thürauf, M.; Lalkovski, S.; Ivanova, D.; Kisyov, S.; Korten, W.; Salsac, M.-D.; Zielińska, M.; Mărginean, N.; Ghită, D. G.; Lică, R.; Petrache, C. M.; Astier, A.; Leguillon, R. in Phys. Rev. C (2014). 90(6) 067301.
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Germanium-gated γ–γ fast timing of excited states in fission fragments using the EXILL&FATIMA spectrometer. Régis, J.-M.; Simpson, G.S.; Blanc, A.; de France, G.; Jentschel, M.; Köster, U.; Mutti, P.; Paziy, V.; Saed-Samii, N.; Soldner, T.; Ur, C.A.; Urban, W.; Bruce, A.M.; Drouet, F.; Fraile, L.M.; Ilieva, S.; Jolie, J.; Korten, W.; Kröll, T.; Lalkovski, S.; Mach, H.; Mărginean, N.; Pascovici, G.; Podolyak, Zs.; Regan, P.H.; Roberts, O.J.; Smith, J.F.; Townsley, C.; Vancraeyenest, A.; Warr, N. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2014). 763 210 - 220.
Abstract A high-granularity mixed spectrometer consisting of high-resolution Ge and very fast LaBr3(Ce)-scintillator detectors has been installed around a fission target at the cold-neutron guide PF1B of the high-flux reactor of the Institut Laue–Langevin. Lifetimes of excited states in the range of 10ps to 10ns can be measured in around 100 exotic neutron-rich fission fragments using Ge-gated LaBr3(Ce)–LaBr3(Ce) or Ge–Ge–LaBr3(Ce)–LaBr3(Ce) coincidences. We report on various characteristics of the EXILL&FATIMA spectrometer for the energy range of 40keV up to 6.8MeV and present results of ps-lifetime test measurements in a fission fragment. The results are discussed with respect to possible systematic errors induced by background contributions.
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A method to correct differential nonlinearities in subranging analog-to-digital converters used for digital γ-ray spectroscopy. Hennig, A.; Fransen, C.; Hennig, W.; Pascovici, G.; Warr, N.; Weinert, M.; Zilges, A. in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2014). 758 69 - 76.
Abstract The influence on γ-ray spectra of differential nonlinearities (DNL) in subranging, pipelined analog-to-digital converts (ADCs) used for digital γ-ray spectroscopy was investigated. The influence of the DNL error on the γ-ray spectra, depending on the input count-rate and the dynamic range has been investigated systematically. It turned out that the DNL becomes more significant in γ-ray spectra with larger dynamic range of the spectroscopy system. An event-by-event offline correction algorithm was developed and tested extensively. This correction algorithm works especially well for high dynamic ranges.
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Isospin Character of Low-Lying Pygmy Dipole States in 208Pb via Inelastic Scattering of 17O Ions. Crespi, F. C. L.; Bracco, A.; Nicolini, R.; Mengoni, D.; Pellegri, L.; Lanza, E. G.; Leoni, S.; Maj, A.; Kmiecik, M.; Avigo, R.; Benzoni, G.; Blasi, N.; Boiano, C.; Bottoni, S.; Brambilla, S.; Camera, F.; Ceruti, S.; Giaz, A.; Million, B.; Morales, A. I.; Vandone, V.; Wieland, O.; Bednarczyk, P.; Ciemała, M.; Grebosz, J.; Krzysiek, M.; Mazurek, K.; Zieblinski, M.; Bazzacco, D.; Bellato, M.; Birkenbach, B.; Bortolato, D.; Calore, E.; Cederwall, B.; Charles, L.; de Angelis, G.; Désesquelles, P.; Eberth, J.; Farnea, E.; Gadea, A.; Görgen, A.; Gottardo, A.; Isocrate, R.; Jolie, J.; Jungclaus, A.; Karkour, N.; Korten, W.; Menegazzo, R.; Michelagnoli, C.; Molini, P.; Napoli, D. R.; Pullia, A.; Recchia, F.; Reiter, P.; Rosso, D.; Sahin, E.; Salsac, M. D.; Siebeck, B.; Siem, S.; Simpson, J.; Söderström, P.-A.; Stezowski, O.; Theisen, Ch.; Ur, C.; Valiente-Dobón, J. J. in Phys. Rev. Lett. (2014). 113(1) 012501.
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Efficiency determination of resistive plate chambers for fast quasi-monoenergetic neutrons. Roeder, M.; Elekes, Z.; Aumann, T.; Bemmerer, D.; Boretzky, K.; Caesar, C.; Cowan, T. E.; Hehner, J.; Heil, M.; Kempe, M.; Maroussov, V.; Nusair, O.; Prokofiev, A. V.; Reifarth, R.; Sobiella, M.; Stach, D.; Wagner, A.; Yakorev, D.; Zilges, A.; Zuber, K.; Collaboration, R3B in The European Physical Journal A (2014). 50(7)
Composite detectors made of stainless-steel converters and multigap resistive plate chambers have been irradiated with quasi-monoenergetic neutrons with a peak energy of 175 MeV. The neutron detection efficiency has been determined using two different methods. The data are in agreement with the output of Monte Carlo simulations. The simulations are then extended to study the response of a hypothetical array made of these detectors to energetic neutrons from a radioactive ion beam experiment.