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    User name R.Michaels

    Log entry time 22:02:16 on December 15,1998

    Entry number 8711

    keyword=HAPPEX asy (?)

    I haven't looked at the setup for awhile, but from home
    I checked some runs taken by the shift. My comments:

    1. Because of recent hardware changes in HAPPEX
    DAQ, the instructions might be obsolete. Ask Etienne.
    From home I made charge asymmetries
    "by hand" with these paw commands

    paw> open_data 8385....... (opens the file, run 8385)
    paw> recover 21........ (recovers the ntuple)
    paw> 1d 101 ' ' 100 -1000 1000......(book histogram)
    paw> nt/pl 21.bcm1r%t...... (see where to put beam-off cut
    and verify bcm is nnot saturating the 16-bit ADC)
    paw> nt/cut 10 bcm1r>2000.....(beam-off cut)
    paw> nt/pl 21.1000000*(bcm1r-bcm1l)/(bcm1r+bcm1l) $10 ! -101
    paw> h/fit 101 g
    Result is BCM1 asymmetry in ppm

    comment 2: What I said on the phone was wrong.
    Asy seems to be varying a lot for the three runs.
    But I didn't take the data and have no idea why.

    run..........BCM1 Asy (or is it ? - hardware changes ?)
    8382......+246+/-60 ppm
    8383......+496+/-71 ppm
    8385......-50+/-75 ppm

    3. The width in the BCM asymmetry is
    presently 2-3 times larger than normal.
    Seems strangely noisy.

    4. If beam does not trip off in a run, pscaler i10 asy should
    be ok. Although Moller measures this asymmetry with
    about 10 times less accuracy than HAPPEX, they have
    been known to agree and it is a useful cross check.