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    User name J. Roche

    Log entry time 00:07:46 on July29,2001

    Entry number 68158

    keyword=schift summary

    SUMMARY :
    smooth shift though the beam charge assymetry is though to maintained low. One should probably not rely on the automatic feedback (performed at the end of each run). Indeed, the assymetry is correlated to the intensity and the intensity varies enought during one given run to produce a large (~200 ppm) drift of the measured charge assymetry.

    **********************************************
    **********************************************
    target -> transverse mode 270 deg
    -> 1/2 wp out
    beam -> toggle
    -> 1/2 wp in

    **************
    16:30 while waiting beam target pol meas.
    epr =41.1%
    nmr=40.9%
    ***************
    17:00 beam back
    fbs on
    raster on
    charge assymetry fb on
    beam position ok (bpm B =-1.8*-1.8)

    run 21358 ->
    ls -ls /adaql2/data2/e99117_21358.dat.0
    ls: e99117_21358.dat.0: Stale NFS file handle
    this data might be lost.

    **************
    20:00
    we have trouble with the charge assymetry feedback. We supect a bad calibration (twice too hight) of the rotatable wave plate slope. A. Vacheret is going to come and try to perform a new calibration using previous data. Antonin come and change the slope in the feedback system to 12 ppm/step.

    ************************
    21:30 epr and nmr measurement
    nmr 38.2%
    epr 38.6 %

    **************************
    stat

    run #electron on left, on right spectrometer
    **357 : 1634, 1470 -> 0.5 h run to check detectors.
    **358 : 3421, ???? -> error in trying to read the right spect file
    **359 : 3501, 3295
    **360 : 3481, 3304
    **361 : 3502, 3410

    total