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    User name Lingyan

    Log entry time 02:18:00 on February24,2001

    Entry number 56900

    keyword=prescale and deadtime error from run 2159 to run 2169

    Some operations on prescale.dat may lead to false reading of prescale factors by espace or end-of-run file. For example,

    1.Change the prescale.dat in the middle of the run and save it.
    2. Have more than one prescale lines even if you comment out the rest ones.
    The espace and end-of-run file will read the first line no matter it was commented out or not.
    3. Strange characters like space et al.

    Change of the prescale factors in end-of-run file from run 2159 to run 2172. One sign of getting wrong prescale factors is weired deadtime for accepted triggers,compared to that for accepted scalers.

    run#.............correct....................wrong
    2159...10/1000/1/1000/1...6/20000/20/20000/1
    2160...1/1000/3/1000/1.....6/20000/20/20000/1
    2161...4/4000/15/4000/1...correct
    2162...4/4000/15/4000/1...correct
    2163...1/3000/3/3000/1......4/4000/15/4000/1
    2164...4/4000/15/4000/1....correct
    2165...4/4000/15/4000/1....correct
    2166...junk
    2167...1/1000/3/3000/1...4/4000/15/4000/1
    2168...8/4000/30/4000/1...4/4000/15/4000/1
    2169...8/4000/30/4000/1...4/4000/15/4000/1