Post-teleconference, re: muSCA treatment and TPC drift

[Tom Banks <tbanks@socrates.berkeley.edu>]

Hi all,

two addendums to answer questions from today's teleconference:

1. I checked my analysis software, and found that I am using the muSCA in
two ways:
   (i) It's incorporated into the union of *all* muSC copy1+copy2+etc.
       hits for the purposes of pileup protection (bank "MUFP");
   (ii) It's used to veto the "good seed" hits formed from the
        intersection of muSC copy1 and copy2, giving bank "MUSC".
So it *is* possible that an increase in the muSCA noise level could be
responsible for jumps in the "TPC w/o muSC" fraction.  I'll look into it.

2. Concerning Steve's question about the anode locations in the drift
distribution, which I don't think I answered very clearly at the time: My
point was that, if you want to use the sensitive volume's 120 mm as the
width for your mustop y-region, then you have to find the sensitive
volume's boundaries within the drift distribution (i.e. the locations of
the upper and middle cathodes).  If you wanted, you *could* calculate
positions from anywhere in the drift distribution (including very early
times), but then you have to increase the y-dimension to 123.5 to include
for the "half-gap", as well as account for the different (and nonlinear)
drift rate within the MWPC region.  I chose the former approach for
reasons of simplicity.

Regards,
Tom