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Table of Contents
DAQ:Mode 2 data loss (Chris)
Severity
We cannot afford losing any triggered data. For absolute x-section measurement GRETINA efficiency is crucial.
Problem
For S800-GRETINA data with GRETINA self-trigger only we find S800 events in Global.dat without corresponding GRETINA event.
Size of problem (from Scott's email)
In a low rate file, the following event counts were found:
11,886 coincident events (s800 and gretina present with correlated timestamp)
719 s800 only events
15 gretina only events (now fixed in S800 daq)
So, ~6% of the decomposed data is missing.
Also, missing gretina data is spread throughout the file, not concentrated at the beginning or end.
Progress
- 5/17/2012: Discussed losses with Mario. Code review and version check to follow.
