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User name Longwu Ou
Log entry time 17:54:13 on July 07, 2014
Entry number 1247
keyword=Negative dead time for some runs
From recent test we saw negative dead time for some runs.
Dead time calculated according to the formula (if only one trigger is
DT = 1 - ps*#Rec/#Scalar
where #Rec is obtained by cutting on evtypebit and #Scalar is total
counts from scaler variable in the tree.
For run 1620, 1624, we get negative dead time from this calculation.
RUN NO. Prescale factor Dead time
1620 ps7=2 other=0 -3.48%
1624 ps7=2 other=0 -2.22%
Trigger 7 was a pulser at about 2kHz in run 1620 and at about 100Hz in
run 1624 respectively.
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