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    User name gilman

    Log entry time 03:01:50 on October 30,1999

    Entry number 29330

    keyword=time needed at 1.95 GeV

    I calculated the event rates with longer replays of our current 1.95 GeV
    data. I find that the rates are 20 k events / Coulomb for gamma d,
    7 k evt / C for e d, and 2.4 k evt / C for gamma p, leading to a need
    for 13 C total charge to get an error of 0.05, including a 5% effect
    for the (simple dipole) spin transport, assuming an analyzing power
    of 0.22 (should be good to ~5%).

    Note 9 C would get us a 0.06 uncertainty, while 6.6 C gets us 0.07.

    The charge fractions work out to be the same as Krishni and I had
    calculated earlier, with poorer statistics replays.

    We take 0.11 C / hour at 30 microamps and 100% efficiency,
    so we need 4.9 100-% efficient days in our scheduled 7 days at this

    We also have ~ 1 day of systematics checks I have in mind,
    plus we have considered the desirability of "2 days" for gamma p
    measurements at this energy.

    It appears clear everything cannot be done.