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    User name R. Michaels

    Log entry time 15:37:49 on December17,2008

    Entry number 253748

    Followups:

    keyword=PVDIS parasite work (I)

    PVDIS parasites on R-HRS. (Transversity may ignore).
    Ramesh, Xiaoyan, and a bit of Bob

    Run 20192 started at 13:21.
    All prescale factors = 1
    Here is the mix of triggers in data file at present.

    T1 0
    T2 1455
    T3 221
    T4 200
    T5 1
    T6 0
    T7 215
    T8 74773
    T9 2776

    So it's mostly T8. One problem is we are somewhat blind about
    rates. We need to revive the standard scaler reading of the
    scint. PMTs (we had borrowed several scalers for Transv.).
    Takes a couple hours of access.

    Another problem is that the rates from PVDIS scalers are absurdly
    low (don't agree with expected pulser rates for 10 kHz and 103.7 kHz
    pulser inputs). Looks to me like the VETO is reversed polarity,
    so it rejects 98.4%. Such a correction yields better rates.
    We may unplug this veto for now; we're not trying to do fine
    asymmetry measurments yet anyway.

    It looks like the T8 rate is approx. 11 Hz. T8 is S1.and.S2 (what
    we used to call T1). It seems the HV crate is ok and drawing current.
    Having the scalers for each PMT is essential.

    Magnet polarities (Q2 and dipole) look correct (negative particles).
    Checked Gaussmeter and NMR.

    Scratching our heads about the low rates and poor data qualities.
    Ramesh will post some plots.