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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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 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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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Atome, Kerne, Quarks – Alles begann mit Rutherford: Wie Teilchen-Streuexperimente uns die subatomare Welt erklären Paetz gen. Schieck, Hans (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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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.