Next: Saving and loading cuts Up: Matrix analysis Previous: Load the environment

Creating cuts

To create a cut you have to define a set of gates. You can do this in several ways, e.g. with the hotkey c or the according command:

tv $>$ cut marker cut enter cursor

The first two markers define the positive gate, whereas the following marker pairs define background gates.

Another way is to enter the markers by their channel or energy. You can switch between channel and energy with the commands:

tv $>$ cut scale marker default

tv $>$ cut scale marker calibrated

tv $>$ cut scale marker uncalibrated

and the marker is set with the command:

tv $>$ cut marker cut enter value

Since you can set only one positive gate by using the hotkey C TV offers a possibility to set further gates with the hotkey GG or the according command:

tv $>$ cut marker gate enter cursor

Another way to define background-gates is the command:

tv $>$ cut marker bg-gate enter value

To perform the cut press the hotkey C or enter the command:

tv $>$ cut create cut

The background gates are weighted against the positive gates. The more background you mark the better it is, because it reduces the statistical error. The background is weighted by gatewidth by default and can be weighted by volume, too. The commands to switch the weight are:

tv $>$ cut weight gatewidth

tv $>$ cut weight fit

It is evident how important it is to choose correct background gates as is shown in figures 5.1 on page , 5.2 on page and 5.3 on page .

**Figure 5.1:** Cut without background gates.
$\begin{figure} \begin{center} \leavevmode \epsffile {pictures/cut-no-bg.ps} \end{center}\end{figure}$

**Figure 5.2:** Cut with good background gates.
$\begin{figure} \begin{center} \leavevmode \epsffile {pictures/cut-good-bg.ps} \end{center}\end{figure}$

**Figure 5.3:** Cut with bad background gates.
$\begin{figure} \begin{center} \leavevmode \epsffile {pictures/cut-bad-bg.ps} \end{center}\end{figure}$

If you want to use the cut markers from another cut in the active cut you can do this with the command:

tv $>$ cut use-marker $<$ index $>$

which copies the gates from cut $<$ index $>$ to the active cut.

If you have found a good set of gates but want to look for an even better one, you can store the current gates and background-gates with the store commands:

tv $>$ cut marker gate store

tv $>$ cut marker bg-gate store

and resume them with the according restore commands.

To perform a new cut you have to delete the gates from the previous cut first. Again you have to separately do it for the gates and background-gates. If you want to delete both you can use the hotkey -C.

Next: Saving and loading cuts Up: Matrix analysis Previous: Load the environment

Andreas Fitzler
7/13/2000