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User name R. Michaels
Log entry time 16:35:29 on January 15, 2009
Entry number 256225
This entry is a followup to: 256222
keyword=re: negative deadtime
For run 5187, I see
Number of events in raw data file (evtype <= 12); 150488
Number of counts in L1A in bbite scalers = 150488, agrees with above (good)
Number of counts in L1A in L-HRS scalers = 198589, disagrees (bad).
The "datamon" GUI uses L-HRS.
BBNormAna presumably uses bbite scalers.
Excess of L1A can cause apparent negative deadtime and could be caused by
flakey cabling, reflections, etc.
On a different note, in run 5187 there seem to be a large amount of extra hits
in fastbus modules. (flags 0xdcfexxxx). Perhaps the experiment doesn't notice ?
A copy of this log entry has been emailed to: kalyan@jlab.org