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    User name R. Michaels

    Log entry time 16:49:20 on November 4,2000

    Entry number 51476

    keyword=re: deadtime calculation bugs (recoverable)

    Regarding the deadtime oddities, I noticed three things:
    1) The datastream contains enough info to compute the
    deadtime correctly, so problems noted are recoverable;
    2) The ``datamon'' software was looking at the wrong scaler
    channels, because we rearranged things. Oops. I fixed it.
    3) I believe the runend.tcl script does not take into account
    the fact that for every T5 there is a T1 and a T3 in scalers.
    Doing this by hand I get approximate deadtimes of
    1062....375 Hz.....3 %
    1063....1660 Hz....16 %
    Keep in mind, deadtime only scales with rate if
    the triggers are random; the above two runs had
    large prescale factors to adjust the rate of T4, which
    then looks a bit like a pulser. I'll let Mark Jones fix
    runend.tcl (assuming I'm correct that its needs fixing).
    I guess it wasn't noticed before because usually
    singles prescale factors are big.