Log entry time 10:21:27 on November 28, 2008

Entry number 251158

Since Brad only turned on last 10 channels, I only plot 10, which were
turned on. The Beam current is 12uA. For each channel, I put geometric
cuts and trigger cuts.

For TDC(Fig 1), red lines are energy deposit larger than 600 and the
green are less than 600. After decreasing the threshold it still gives
the same shape. So I would say pion can hardly induce the Cherenkov light.

For ADC(Fig 2), red lines are the counts chosen by the cuts
BB.ts.ps.e>800&&(BB.ts.ps.e+BB.ts.sh.e)/BB.tr.p>800.
which is a very strict cut to choose clean electron. The green lins are
chosen by
BB.ts.ps.e<400,
where there are only little electrons.

So compared with previous plots we got, I think the pion cannot induce
the Cherenkov light in our gas. The main problem is still how to shield
the PMTs.

PS: From the plots I think there is some problem on channel 17. Maybe the
PMT doesn't work. Does somebody know about it?

TDC

ADC