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    User name R. Michaels

    Log entry time 15:25:58 on August 7,2006

    Entry number 178066

    This entry is a followup to: 177995

    keyword=helicity less sensitive to timing

    I found one problem with the helicity code. It computes "fT0"
    using a function TMath::Floor(x) where x is an expression that
    involves calibration constants. Replacing x -> x+0.5 makes this far
    less sensitive and the warnings occured only 3 times in 1 million
    events of run 2273 (a high rate run with 25% DT). I investigated
    one of those remaining episodes: It appears that the timestamp
    data are ok but a helicity transition occured 12.9 msec too early.
    That's a mystery, but if its only 3 in a million I guess it's ok.
    We perhaps should assign helicity=0 to such mysterious episodes
    but that's not what the code does now. It just issues a warning.

    The conclusion is that the experiment will have fun analyzing the
    data.