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    User name Sharon Beck

    Log entry time 00:01:56 on June24,2007

    Entry number 206445

    keyword=Shift summary

    16:10 - Running smoothly with 45uA.
    There was a mometary beam trip
    Radiator temperature: ~150C (reduced a little with the beam trip)

    run 1489 - 1492: ,
    run 1493: Current: 45uA, Radiateor OUT, trigger rates are hige, DT=19% (JUNK)

    Beam current was increased to 50uA
    We changed the prescale factors such that the rate would be:
    T1~100Hz, T2~50Hz, T3~100Hz, T4~50Hz, T5=all
    ps1=20 ps2=50 ps3=14 ps4=2600 ps5=1

    run 1494: Current: 50uA, Radiateor OUT, DT=2% -JUNK run:
    We noticed the temperature on the radiator is rising (more than 300C and rising !!!) Apparently the radiator was not moved completely out
    The lines on both sides of the object should be on the same level (I asured that the lines on both sides of the number/"UL" would be on the same level). The beam probably hit the Aluminum frame and it was heated.

    We asked MCC to take the beam off, the radiator was moved completely out of the beam, then the beam went back on to 50uA and we started a new run with the previous prescale factors:
    ps1=2 ps2=4 ps3=2 ps4=600 ps5=1

    run 1495: Current: 50uA, Radiateor OUT, run time~ 1 hour.

    We put radiator back in (5 on scale), beam changed to 45uA.
    ps1=15 ps2=30 ps3=9 ps4=2000

    run 1496-1498: Current: 45uA, Radiateor IN, DT=2%

    21:10 - We stopped the run (1498) for 5-10 minutes due to calibration runs with high current to Hall C.
    21:20 - Nothing happened to the beam, so we'll keep taking data while we still can.

    run 1499 - ~226000 events. During that run Hall C changed the current in steps. The beam to Hall A was 45uA.

    21:52 - Got the beam back and started a new run (1500)

    run 1500: Current: 45uA, Radiateor IN

    run 1501: Current: 50uA, Radiateor OUT, DT=3-4%

    ---This was the last run with He3 target@2.5 GeV------------
    All together there were 21.5M events collected with radiator IN
    6.6M events collected with radiator OUT
    (runs: 1453-1501)
    ---------------------------------------------------------------

    We change to Carbon target and run with radiator out (1502)