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User name paschke
Log entry time 01:01:47 on August24,2009
Entry number 285618
keyword=focal plane distribution in left arm
HAPPEX detector seems to be plainly seen in the shape of the T1 trigger on the left arm. (See plot below, left column is first trigger bit, right colum in second trigger bit.) So the inefficiency is not a misdefinition of trigger. But there is clearly a problem. Bob's new theory is that the S0 PMT voltage is too low (or threshold is too high). It must be something like that.
This trigger comparison couldn't be made for the -3% momentum setting, because we had prescaled the non-T2 triggers into nothingness.