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    User name jpchen

    Log entry time 00:28:29 on May13,2009

    Entry number 272886

    keyword=swing shift summary

    Swing shift summary:

    Shift workers: J. P. Chen(SL), Y. Zhang (TO), X. Deng (3rd)

    16:00 Hall in controlled access to finish experiment switch-over.
    17:45 Requested for sweep.
    18:15 Hall in beam permit. moved to empty target for beam tuning.
    18:40 Beam through Compton and position at (-0.5,2) for both BPM A and B. Asked for harp scan.
    18:45 harp scan is done. moved to BeO. Checked BeO spot ok.
    18:57 Raster on 7x5 MCC, 4x4 ffrom spot++.
    19:15 Evacuated reference cell. adjusted pressure gauge. filled
    with 1 atm D2 (re-adjusted pressure gauge. moved to reference cell.
    19:30-20:10 Finding center/edge with reference cell:
    Check rate with 2 uA, raster 4x4, then 6x6.
    Saw it hits edge. Moved x from -0.5 to 0 then to -1.0, good.
    back to 4x4.
    20:10-20:30 Find center/edge for polarozed He3:
    Moved to pol. 3He, check position x=-1.0 with raster 4x4 then
    6x6, see a little bit of edge, moved to x=-0.5.

    With the above checks, we will keep beam position at (-0.5,+2).

    20:30 Moved to Multi-12C, checking rates. adjusted prescale factors.
    Took production data on Multi-foil 12C target. 1.5 millon events on left and over 2 million events on right.
    Left+BB, with a little over 1KHz rate, deadtime is <20%.
    Right+ND, with 4KHz rate, deadtime is 24%. Tried to change pre-scale factors, seems not change deadtime. Turned out that we had a wrong PS data file. Once we had the correct file, changed prescale T1=2
    for run 21058, deadtime is much smaller (a few %).

    21:10 Moved to reference cell, filled D2 to 100 psig.
    Started checkout of BB on reference D2 target. Miha and Jin Ge are doing the checkout. Right arm+ND are taking production data during this time period.
    Left+BB deadtime: with only ~500 Hz DAQ rate (5uA on 100 psig D2 target, with PS5=1, PS6=2, PS3=20,PS4=8), deadtime is ~20%, similar to the previous situation with over 1KHz DAQ rate, 5 uA on multi-12C.
    JinGe finished his part earlier. Miha is still working on his part of checkout at the end of the shift.

    Some small issues found from the data reply, logged in several Halogs.

    Run summary: (5 uA)

    Left 2136/2138, production on multi 12C, .6M/1.5M. 42%/19% deadtime.
    2141-2155, BB checkout.

    right 21056, production on Multi12C, 3M, 24%
    21058 production on multi 12C, 0.6M, 6%
    21059/21060 production on D2, 4.6M/3.3M, 6%.