[d2n-analysis-talk] BB Cerenkov hardware threshold

[Diana Parno]

I'm wondering what the hardware threshold on the BB Cerenkov was  
during the experiment, in terms of number of photoelectrons. I found a  
HALOG entry placing the threshold at -0.070 V:

http://www.jlab.org/~adaq/halog/html/0902_archive/090210201819.html

Brad's Cerenkov tech note talks about gain-matching the PMTs to place  
the one-p.e. peak at about 50 mV, which would put the threshold at  
about 1.4 p.e. On the other hand, page 4 talks about a 3-p.e.  
threshold, and I am not sure from context whether that's supposed to  
be a hardware (online trigger) threshold or a software (offline cut)  
threshold. If the threshold is 1.4 p.e., do we have a rough idea as to  
the online pion rejection factor? (If it's 3 p.e., then Matt's study  
from last month would give that factor, if I'm not mistaken.)

Best,
Diana