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    User name Lindgren

    Log entry time 17:04:19 on January11,2005

    Entry number 138971

    keyword=Day shift summary

    Day shift summary: Tuesday 11 Jan 2005
    kinematics set for H(e,e'p) in HRS_left and neutron detector
    neutron detector at 50 degrees and 15 m.

    08:00 Determining adjusted HV levels on the neutron detector (Peter M and Eli P)
    08:00-09:00 runs 1690-1693
    change the HV levels
    09:27 start run 1694 w/new HV levels
    9:30-10:00 runs 1694, 1695
    change HV levels
    10:10 start run 1696
    10:22 start run 1697
    vary HV levels between runs 1697, 1698 and 1699

    10:50 set final HV levels
    10:55 start run 1700 (250K events)
    11:10 run 1701 (124K events) ended early at 11:20 to allow more time for the sieve slit run
    11:22 put in sieve slit
    11:25 sieve collimator sticks. back up a little and then try again.
    sieve collimator at 0.3698 (0.4mm off)
    11:28 start run 1702
    increase beam current to 3.5 uA
    11:33 increase beam current to 4.5 uA (unrastered on LH2 target)
    12:15 end run 1702 with 61K events
    reduce beam current to 2.5 uA
    remove sieve slit
    change to T7 only trigger with ps7 prescale at 64K
    12:17 start run 1703
    64K is too high a ps factor. change ps7 to 10K
    this will give 300 Hz for trigger 7
    12:20 start run 1704
    12:30 end run with 250K events
    That's it for beam for this shift.

    Next up: move the neutron detectors and the HRS and change HRS polarity.
    Neutron detector moved to 99 degrees and positioned behind BigBite
    2 inch think lead shield moved and bolted into place in front of neutron detector
    4:05 Techs out of Hall
    Request beam permit
    16:30 Going down to fix channels and power cycle - ROC4