The sample events from short gas cherenkov are defined by cuts:
"GC sample" electron events:
1000 spec_l.gas.adc_sum_t
4000
"GC sample" pion events:
spec_l.gas.adc_sum_t 10000
Figure shows the PR layer 1 energy vs. PR layer2 energy
for "gc sample" electrons (top, left) and "gc sample" pions (top, right). Similiar to the right arm,
strict two-dimensional cuts in PRL1/PRL2 are used to define "PR sample" electrons and "PR sample"
pions, which are:
"PR sample" electron events:
spec_l.prl1.cl_e2100
spec_l.prl2.cl_e650
spec_l.prl1.cl_e0.4+spec_l.prl2.cl_e
2000
"PR sample" pion events:
100 spec_l.prl1.cl_e
300
50 spec_l.prl2.cl_e
200
The two plots in the middle show these two cuts for all events, without any cut in
gas cherenkov. The pion events are very low so they are plotted with a
different scale in the two plots in the bottom.
The "GC sample" electron events are different from the definition on the right arm.
Cannot do a cut in pion rejector energy to remove possible pions from this sample and
preserving all good electrons at the same time.