• Main INDEX
  • Monthly INDEX
  • PREV
  • NEXT

    User name R. Michaels

    Log entry time 07:41:15 on March 02, 2006

    Entry number 164742

    This entry is a followup to: 164736

    Followups:

    keyword=re: helicity (actually QRT) DISASTER

    As far as we know, the "helicity loss" is all due to missing a
    QRT signal. Now, the results in halog 164736 are terrible, and I
    don't think you can run this way (might lose 10 minutes in a run).
    I also don't like the idea of ignoring QRT, which might be a workaround.

    One issue is that in halog 164685, before I went to bed, I reported
    seeing only 3.3 sec losses in 4.8 hours. However, nobody was running
    the DAQ because there was beam tuning. Here might be a clue, because
    as far as I can tell from the halog there was no beam ON target (is
    that right ?). But on owl shift there was beam on target and a much
    higher failure rate. If we can establish that the event helicity info
    is also missing QRT (Rich, please check) then this points to a module
    in the hall that handles QRT which is, perhaps, getting hosed by
    radiation. It's my guess du jour. What's the loss rate when there is
    no beam at all in the hall ?

    A copy of this log entry has been emailed to: rsholmes@jlab.org,jones@jlab.org,bogdanw@jlab.org