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    User name E. Schulte

    Log entry time 18:18:12 on November 03, 2007

    Entry number 211967

    keyword=Back to taking data after along interruption of service

    After a rather frustrating, for all involved, interruption of service,
    Hall A is back taking data.

    During the scheduled interruption of service for Hall B beam studies &
    setup for 5 Pass things seemed to have gone down hill. This followed a
    rather vexing Swing shift on 11/02 after the Hall A pass change from 1
    pass to 2 pass. The beam studies were abandoned after a while. I seems,
    from the ELOG, that the accelerator was having vacuum problems which
    required expert assistance. As of 08:30 today, a call to MCC revealed
    that we had had a poor beam tune during the preceeding Owl shift
    (supported by the insane compton rates). They backed out of that tune
    and retuned all of the Hall's transfer lines. Several other issues
    followed (difficulty delivering high current to Hall C, etc.).

    Around about 14:30 MCC was delivering beam back to the Hall A. A small
    amount of production data was taken. I requested a harp scan shortly
    after beam delivery resumed (around 15:50). The crew had been retecent
    to request the scan since earlier in the day they [the crew] were
    informed it could not be performed. This was probably because we didn't
    have any beam in the hall at the time the crew requested it. I'm not
    sure why the crew requested the harp scan...probably miscommunication
    about the status of beam delivery to the hall.

    Anyway, MCC spend about an hour after request of the harp scan doing
    something that involved tuning beam to the hall. The crew cheif then
    called and asked again what it was that we wanted from the Harp scan, and
    which harps we wanted scanned. Also, the OTR target needed to be put in
    place. The OTR was re-inserted to its proper location, and the signal
    reappeared. A pretty crummy one, though.

    After some more work to get the harp scan accomplished, the OTR signal
    (at 5uA) looks much better than it did initially. By 18:00 the harp
    scans were finished, the BPMB position was re-centered, and the raster
    zise is re-checked. The raster MCC values needed to be increased a bit.
    The new MCC values for the raster are to request 5x6 for a raster size
    as determined by spot++ as 2x3.

    With the raster on at 50 uA, the OTR looks a little crummy again. And
    the beem may be getting more trippy at the high current delivery.