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    User name R. Michaels

    Log entry time 13:16:25 on November 24, 2009

    Entry number 302338


    keyword=near-term Compton plan

    After discussing with P. Souder and Alex here is a near-term Compton plan

    Last night Alex put in the Edet. I'm not sure what the result was (still
    a bit noisy but not as bad as before). I guess he'll post spectra later.

    The noise in the accum0 of FADC is 4 times higher than we need. But this
    means we are close. Meanwhile we see asymmetries with accum2 which uses
    a threshold cut which is undesirable. There's a decent chance we'll be
    in good shape if :

    1. Reduce background in Edet (also reduces in photon det ?)

    2. Install the smaller-hole collimator (planned for next week)

    Regarding the Edet, one piece of info we need soon is how much the
    background reduces if we close the slits. If this causes a dramatic
    reduction then more injector tuning is needed, using the Edet as the
    monitor to feedback on. We don't plan on any major tuning before
    Monday, but a brief run with closed slits after Alex is ready is

    Getting the Edet to work at 6 GeV is very desirable. Having the
    zero-crossing will help pin down the B*dl and provide a check on
    the lower-energy results, both HAPPEX-3 and PREX.

    A copy of this log entry has been emailed to: souder@physics.syr.edu,camsonne,paschke