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A minor bug in ascascreen to do with T_SAA and T_DY_NT

We have discovered a minor bug in ascascreen:

The current version of ascascreen does not apply the correct value of
T_SAA and T_DY_NT. Instead of converting 4 readout times into the
appropriate number of seconds, ascascreen always sets T_SAA and T_DY_NT
to be greater than 4 seconds, regardless of clocking mode. This is not a
serious bug because applying the T_SAA and T_DY_NT criteria, even
correctly, does not screen many events. Since ascascreen does not prompt
the user to set T_SAA and T_DY_NT, the way around the problem is to edit
the _mkf.sel file. Specifically, you should first run ascascreen as
usual, but type "ascascreen -q" instead of "ascascreen". This will cause
ascascreen to stop before running xselect. Second, type "ls" to identify
two files which ascascreen has just produced: the _mkf.sel file, which
contains the screening criteria, and the .xco file, which contains the
xselect commands. Third, use an editor to overwrite the correct values
of T_SAA and T_DY_NT in the _mkf.sel file (16, 32 or 64 seconds for
1-CCD, 2-CCD and 4-CCD modes, respectively). Finally, run xselect: after
choosing a session name, type @ followed (without a space) by the name
of the .xco file. By following these steps, you're effectively running
ascascreen as usual, but with an interruption in the middle to correct
the bug.

Charles Day, ASCA GOF