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    User name paschke/snyder

    Log entry time 19:42:43 on June22,2004

    Entry number 126663

    keyword=opportunistic source studies

    CHL crash, so opportunistic source studies in the 100 keV region.
    We set the bpm gains in crate iocse11 to match the gains we used
    in studies May 25th.  At that time, the bpms were fine with 40 uA,
    but most are "unlocked" (signals are too low) even though we are
    running 50 uA.  Strange.  Our data looks fine, by the way, so I
    guess I won't worry about it.
    There was a spot move this morning also, so getting 50 uA was no
    problem. By the end of the tests (about 2.5 hours?) the current had
    dropped to 40 uA!
    Run 2371 - checking BPMs in injector, changed PC voltages at end of run.
    Run 2372 - PITA scan, IHWP=OUT, RHWP=2250, PC centered on "ideal" voltages:
    Delta   PC pos   PC neg
       0     5.405   6.388
     100     7.072   4.721
     200     8.739   3.054
    -100     3.738   8.055
    -200     2.071   9.722
    Results: PITA slope approx. -3.4 ppm/Volt.  
    	1I02 DeltaX about .57 nm/V, DeltaY about -0.3 nm/V
    Run 2373 - killed to restart et_server.  Went to Beam line configuration.
    Run 2374 - RHWP scan (IHWP=OUT, PC pos=5.405, new=6.388)
    results: charge asymmetry shape about as expected.  Position 
    differences large (1 um in 1I02, 2 um in 1I04) and pretty much
    no response to RHWP at all.
    Run 2375 - RHWP scan, with 100 V PITA offset (IHWP=OUT, PC pos= 7.072, neg=4.721)
    results: position sensitivity to RHWP, but around 1/3 that of
    	the "constant" position difference offset (for x, much
            less sensitivity for delta y).
    Run 2376 - IHWP->IN, PITA scan. centered on "ideal" PC voltages,
    Delta  PC pos  PC neg
        0  3.931   6.658
      100  5.598   4.991
      200  7.265   3.324
     -100  2.264   8.325
     -200  0.597   9.992
    results: slope in Aq =10.6 ppm/V, 
    	at bpm1I02 position diff slopes are DeltaX = -2.2nm/V, DeltaY = 1.3nm/V
    Run 2377 - RHWP scan (IHWP=IN, PC pos = 3.931, PC neg = 6.658)
    this was interrupted after scanning 130->180 degrees, as the CHL
    was returning and they were ready to use the beam.
    results: large position differences remain, comparable to IHWP=out 
    scans.  Position differences are again totally insensitive to
    RHWP angle.