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    User name J. Singh

    Log entry time 23:38:58 on August23,2003

    Entry number 113037

    This entry is a followup to: 112900

    keyword=background correction spreadsheet

    Since kin 9, we've been using a spreadsheet to help us calculate/monitor our background rates. For each kinematic, it outputs the total number of CODA events needed given details about the reference cell = empty run and the first polarized 3He run for that kinematic. The formula used was correct, however, a clerical error in making the spreadsheet perhaps caused us to overestimate our background and take some more events than we needed for some kinematics. For kin 9, this mistake was caught early and fixed for the whole kinematic. However, after reviewing the spreadsheets for kin 10 & 12, it appears that both contained the same mistake. Since kin 12.13, this has been rectified.

    for inquisitive minds:

    CODA = (runplan)*(0.35/P_target)^2*(0.80/P_beam)^2
    [(good 3He envents)/(replayed 3He events)-(good ref cell empty events)*(3He BCM)*(ref cell T1 rate)/(replayed ref cell empty events)/(ref cell empty BCM)/(3He T1 rate)]