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    User name R. Michaels

    Log entry time 01:53:07 on August14,2005

    Entry number 151807

    Followups:

    keyword=cavity phase study data

    Starting with spectrometer run 2423 we did a series of runs
    with different phase offsets on the BPM cavities #2 and #3.
    Note, I think the BSY BPMs (cavity #1) X,Y output are not working.
    Perhaps needs an IOC reboot ? The ones near the target are fine.

    The idea of the scan in phase is to see where the raster pattern
    might flatten. Going from one extreme (20% of the slider GUI
    scale) to the other (80%) makes a dramatic change which is hard
    to describe (distorts the spectra). Below are the runs.

    Gains don't change during this.
    Upstream and Downstream gains are identical.
    BCM pre-gain 11, post-gain 1024
    X pre-gain 9, post-gain 18000
    Y same as X.

    Run ......... Phases
    ............ Upstream Monitor ......... Downstream Monitor
    ............. X ....... Y ........... X ......... Y
    Nominal Start Values:
    2422 ........ -12764 ... 9992 ...... 14420 ..... 11084
    Now we change:
    2423 ........ no good
    2424 ........ -24971 ... -23753 ..... -24483 .... -23509 ... 20%
    2425 ........ +24240 ... +25753 ..... +27650 .... +26676 ... 80%
    2426 ........ 365 ....... 852 ......... 609 ...... 1827
    2427 ........ -13764 .... 8161 ....... 13277 ..... 8161
    2428 ........ -12302 .... 10110 ...... 14251 ..... 10110
    2429 ........ -10841 .... 11571 ...... 16200 ..... 13033
    2430 ........ -9866 ..... 12059 ...... 16688 ..... 13520
    2431 ........ -8892 ..... 13033 ...... 18637 ..... 15957
    2432 ........ -3532 ..... 6212 ....... 19611 ..... 4263
    2433 ........ -1583 ..... 4263 ....... 18637 ..... 1337
    2434 ......... 852 ....... 7674 ...... 21073 ..... 2314
    2435 ......... 6699 ...... 12546 ...... 2070 ..... 6699
    2436 ......... 11084 ..... 15469 ...... 4506 ..... -9379

    Until further analysis, here's where I leave the phases:
    ............. -12790 .... 9623 ...... 14251 ..... 11084