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    User name R. Michaels

    Log entry time 06:42:50 on June10,2001

    Entry number 62754

    keyword=charge asymmetry feedback problems

    I don't think the feedback on charge asymmetry is doing anything.
    As far as I know, the evidence for functional feedback would be
    twofold: 1) The asymmetry bounces around zero, and 2) There is
    a readback of the waveplate we are allegedly rotating, EPICS variable
    is "psub_aa_pos" from server 129.57.255.4

    This variable is put into Parity DAQ data stream and remained 600
    all night in spite of our attempts to feed back. Also, the asymmetries
    remained around -300 ppm (see below). The MCC crew chief thinks
    he may have found a control GUI that was disabled... will ask J. Grames
    later this morning. Another weirdness is the time stamp; as others have
    noted, it is always displaced from the present time.

    Antonin found that the cut logic in Parity analyzer is wrong; as soon
    as beam trips it quits analyzing events. He is working on this.

    Asymmetries for two systems.
    Parity Run......A (ppm)...........Spectrometer Run......A (ppm)
    708.......... -217 +/- 32......|......20508............ -383 +/- 65
    710.......... -282 +/- 34......|......20510............ -224 +/- 45
    711.......... -346 +/- 46......|......20511............ -316 +/- 36