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User name johna
Log entry time 00:01:55 on November 1,2001
Entry number 75522
keyword=VDC track/multiplicity histograms.
The VDC histograms in the detector analysis have been giving a large number of zero track events, and a large number of 2,3,4... track events. However, even though almost 3/8 of the events have zero tracks, there were very few events with <5 hits per plane. The zero-track events come from event types 2 and 4 which are not analyzed. However, even though they are not analyzed, the histograms are still incremented. It appears that spec_e.track is cleared between events, and so the histogram is incremented at zero. spec_e.*.mult is apparently not cleared, so the histogram is filled with the value from the last analyzed event.
If we can update the kumac so that histograms are filled only when the event is actually analyzed, then we might want to analyze only coincidence events for the detector kumac, as this will give a better idea of the efficiencies for the real data. I'll take a look at this tomorrow (unless someone else wants to fix it up before then).