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    User name R. Michaels

    Log entry time 21:38:55 on October14,2010

    Entry number 334920

    keyword=LH2 rates, run 7369

    Run 7369 .... LH2 target ... Start with 3 uA

    During this run, scalers are recorded, but we write the
    rates by hand here. This could be analyzed better offline.

    Rates
    T1 ... 3300 Hz
    T2 ... 2000 Hz
    T3 ... 37 Hz ... this is a correct rate now (using 103.7 kHz clock)

    Patricia runs spot++ to verify 4x4.

    Chasing a hypothesis that perhaps BCM is nonlinear

    BCM raw rates
    At 3 uA .... D10 = 87 kHz .... U10 = 38 kHz ... D3 = 28 kHz ... U3 = 25 kHz

    At event 13 K we ask for 10 uA
    T1 = 8200 Hz
    T2 = 5200 Hz
    T3 = 105 Hz
    D10 = 2.8e5 ... U10 = 1.22e5 ... D3 = 89 kHz ... U3 = 80 kHz

    Beam off .... (near event 58 K in run 7369)
    T1 = 1200 Hz
    T2 = 670 Hz
    T3 = 6 Hz.

    Scaling by current and subtracting beam-off pedestal
    the expected rate at 3 uA is (105 - 6) * 0.3 = 30 Hz
    The observed rate at 3 uA is (37 - 6) = 31 Hz
    They are consistent. Therefore BCM looks ok at the 10% level
    at least.

    But Carlos thinks this should be slightly above 57 Hz.
    We seem to be missing a factor of 2.

    21:18 ... At event 65 K we ask for beam 10 uA again.
    Let run 7369 run for awhile ...