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    User name R. Michaels

    Log entry time 03:14:27 on June15,2010

    Entry number 326637

    Followups:

    keyword=dipole scan: Up

    L-HRS Dipole scan in the Upward direction.
    Regulator off. Adjust the dipole current.
    R-HRS not touched, so it's still production.

    Integrating mode.
    For each point, do two runs: the normal HV and HV+300 (about)

    More specifically
    det4 at card 2.2 = 622 (normal) and 900 V (higher)
    det3 at card 2.4 = 695 (normal) and 1000 V (higher)

    ---------------------------------------

    Run 4541 = last production run.
    det3 and det4 signals are about 100K channels

    Run 4542 tried the higher V's.
    Saturated the detectors. I guess that was expected.

    Below, "Amps" is the set point. The readback is different.
    The p0 changes in a way that's consistent with percentage.

    Dipole ........ Run .............. det3 ...... det4
    % ... Amps .............. HV ... signal ...... signal

    +1% .. 359 ... 4543 .... norm ... 193 ...... 112
    +1% .. 359 ... 4544 .... high ... 1325 ..... 877

    +2% .. 362 ... 4545 .... high ... 1526 ..... 1040
    +2% .. 362 ... 4546 .... norm ... 210 ...... 132

    +4% .. 369 ... 4547 .... norm ... 1137 ..... 633 (higher, curiously)
    During run 4547 we asked for beam off 1 min.

    I'm concerned that the HV changes causes some non-reproducibility
    here. So we will continue with normal HV, repeat some points,
    and then do higher HV later.

    Run 4548 is junk.

    +7% .. 380 ... 4549 .... norm ... 404 ..... 294

    +10% .. 391 .. 4550 .... norm ... 160 ..... 110

    +15% .. 408 .. 4551 .... norm ... 9 ........ 2
    Asked for a beam off during run 4551

    +20% .. 426 .. 4552 .... norm ... 5.7 ...... 0

    +25% .. 444 .. 4553 .... norm ... 6 ........ 1

    +30% .. 462 .. 4554 .... norm ... 3.7 ..... -1.5

    Next we repeat some of the lower momentum settings. Still normal HV.

    4% .... 369 .. 4555 .... norm ... 1058 ... 605

    Runs 4556 and 7 are junk. CODA problems.

    2% .... 362 .. 4558 .... norm ... 230 ... 137

    1% .... 359 ... 4559 ... norm ... 195 ... 114

    0% .... P0 regulated ... 4560 ... norm ... 1.02e5 ... 1.03e5

    Next we go to the higher HV (900/1000) and do some of the scan

    1% .... 359 .... 4561 ... high ... 1374 ... 924

    4% .... 369 .... 4562 ... high ... 6484 ... 4328

    7% .... 380 .... 4563 ... high ... 2745 ... 2210

    10% ... 391 .... 4564 ... high ... 975 .... 761

    15% ... 408 .... 4565 ... high ... 46 ...... 27

    During run 4565 we ask for beam off for a minute to measure pedestal.
    The pedestals are 9.5 and 4.8 for det3 and det4 with this HV.

    20% .... 426 ... 4566 ... high ... 33 ...... 19

    Did another pedestal (beam-off) check during 4566.

    25% .... 444 ... 4567 ... high ... 50 ...... 27

    30% .... 462 ... 4568 ... high ... 28 ...... 14

    03:14 ... go back to nominal P0, dipole regulation on.

    The data looks pretty good. I'll plot it later.
    On to the next run plan ...