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    User name Ent

    Log entry time 10:02:30 on April 8,2000

    Entry number 38062

    keyword=shift summary

    Initial hours of shift are spent to determine the correct polarities of the three Moller
    quads. Two of the magnets were determined to be of the wrong polarity (the power
    supplies were swapped during maintenance). The moller beam polarization
    measurement was 63%, while the Mott had shown 73%. That indicates that the
    Wien angle is not what it is supposed to be to get roughly equal polarizations in
    Halls A and B. MCC wnats the PD to give authorization, and the PD wnats us to
    verify with the RC of Hall B (although this *was* decided in meetings earlier).
    In the meantime MCC gets RF problems such that things get delued until about
    6 am. Then we decide to just leave it like this, this is apparently too difficult, we will
    just run with 63% polarization. The moller guys take off, we start determining beam
    position and raster. The spot position is 0.5,-1.5 mm off from the BPMB position.
    The raster size has to be modified to be "+/-2.5,+/-1.5" to obtain a 4 by 4 mm2
    raster size according to spot. Note that two hours later totally different values were
    needed to get the same raster size according to spot... Something funny is going on...
    In practice only 2.5 hours of useable beam, for the rest problems with Moller quad
    polarities, trying to convince the PD that the Wien angle should be changed, and
    beam spot checks. Not very productive.