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    User name Reitz

    Log entry time 17:21:08 on July19,2001

    Entry number 66751

    keyword=right arm deadtime

    Checked the Trigger of the right arm because of the high
    deadtime (12% with cosmics) in this arm
    we've noticed some double pulses on the copy of T1 going into the scalers
    used to calculate the deadtime.
    => this high deadtime is not real, but caused by multiple counting of
    single events.
    During the last long maintenance period i have decrease the output width
    of the discriminator of the left scintis to 40 ns, which is
    short, but should still be fine for forming the trigger.
    Increasing it to 60 ns (same value as right discr.) decreased the number of double pulses.
    Further increase to 90 ns (now for both discriminators) led to a further improvement.
    Nevertheles, still some double pulses remain.
    Feed channel 32 of the normalization scalers with a cleaner copy of T1, which
    can also be used for deadtime measuring from now on.
    Another independent methode to get the total deadtime is using the edtm
    system. (This system was running since the start of experiment, and so can
    be used to get the deadtime of these suspicious runs.)