[Halld-online] Potential issue with F125 in run 2931

David Lawrence davidl at jlab.org
Fri May 1 12:45:15 EDT 2015

Hi All,

  It looks like something strange happened part way into the one big run we took last weekend (run 2931).
Sometime in the middle of file 93 the F125 modules suddenly started emitting 12 event header words
per event. Previous files looked to have just one event header per module per event.  A cursory inspection
indicates that this happened for all F125 modules in all crates. One module, (rocid=53, slot=4) had
an itrigger value for the 3rd event header that was always 1 greater than the other event headers
from that module. This pattern persisted until the end of the run. Subsequent runs seemed OK.

At the moment I do not see any issues with the other module types. I also can’t say whether all of the
F125’s started this behavior at the exact same event. I wanted to share this in case someone has
some insight as to what might have happened. Thanks to Justin for pointing out that we were getting
errors here. 


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