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    User name brads

    Log entry time 12:12:25 on February 18, 2007

    Entry number 193999

    Followups:

    keyword=Run Plan for Sunday DAY, SWING

    If you haven't already: please read and sign the COO, ESAD, RSAD (black
    binder).

    Shift Leader: As there are only two people on shift and the TO duties are
    extremely light, the TO will take the role of the usual "3rd" (replay,
    start/stop runs, etc). Please be sure to do an online replay of every run.

    I'll check in with you periodically during your shift, but please read and
    understand the following. Page me (5411) if you have questions.

    You will take over from the previous shift continue the program of marching
    through these kinematic points:

    - Kinematic K (72.0 degrees) -- in progress as of 10am Sunday
    - Kinematic L (78.0 degrees)
    - Kinematic M (84.5 degrees)
    - More to come... The rates are rapidly dropping to zero so we may skip
    point M (and maybe L) and do a few more intermediate points at smaller
    angles.

    Take 2 runs per target, 45 minutes/run.

    Please halog a dp spectrum for the first Lithium and Boron run at each
    kinematic point.

    Beam currents are limited to (raster always on):
    - Target MAX Current Raster
    - Ta 22 uA 1.5x2 (MCC: 10x2)
    - Carbon 10 uA 1.5x2 (MCC: 10x2)
    - Boron 4 uA 1.5x2 (MCC: 10x2)
    - Li 5 uA 1.5x2 (MCC: 10x2)
    NOTE: Do _not_ exceed 5 (five) uA on the Lithium -- the target could melt!

    ----------------------------
    General instructions follow:
    ----------------------------
    The list of kinematics is on the bulletin board to the left of the
    whiteboard.
    - The LHRS is the one that changes angle. The RHRS stays put.
    - Please do _not_ adjust/tweak/correct/update the momentum settings for
    either arm. The magnet readbacks are correct even though they show up
    red. See
    the screen snapshot taped above the "Hall A Tools" monitor for reference.

    Do an online replay for both arms for every run. Note that the green
    'reference' histos will not match unless you know how to modify the
    detectorL.cfg, detectorR.cfg 'golden' file entries and pick an earlier run
    with the same target and kinematics. Use your best judgment and/or manually
    bring up another online GUI for a similar earlier run if you think something
    is really wrong with an online histogram.
    NOTE: Do NOT edit anything with a brain-damaged editor that line wraps the
    text by default (ie. pico, nano, etc.).

    Unless instructed otherwise, start a full replay (ie. replayFull.C,
    replayRightFull.C) for ONE run per target at each kinematic point. Do your
    best to distribute the replays across multiple computers (adaql3,4,5,6,7 are
    available).

    Double check the beam spot on target using raster++. Note that the BMPs (and
    hence raster++) will not work correctly for beam currents below 0.5 uA.

    The current you want to run on the other targets should be 'self-limited' in
    order to keep the left arm prescale in the single digits, or to keep the
    right
    arm VDC efficiencies in good shape and the VDC currents below 10 uA (see
    below), but don't exceed the listed maximums in any circumstance. Please make
    sure the raster is on at all times for the Li target.

    We want the prescaled rates on T1 and T3 are roughly 1 kHz for all
    kinematics/targets.
    - prescales for T2, T4 should give 20-100 Hz for those triggers, but keep
    . ps1 >= ps2 and ps3 >= ps4
    Adjust the beam current to keep the prescale on the left arm in the single
    digits where possible (ps=1 is best).

    Keep an eye on the VDC currents (Hall A Tools GUI) and make sure they stay
    below 10 uA (15 uA is the absolute maximum). The right arm will be the
    limiting factor since you may want to increase the beam current to keep the
    left arm rates reasonable as the LHRS moves to larger angles.
    ! VDC currents are displayed on Hall A Tools GUI
    ! Watch the VDC efficiencies from the online replays. If you see big dips
    in the efficiencies due to the elastic peak, reduce the beam current if
    possible. An example of poor efficiency can be seen at
    <http://www.jlab.org/~adaq/halog/html/0702_archive/070215021758.html>

    Don't hesitate to page the RC if you have any questions/concerns.


    A copy of this log entry has been emailed to: kwang@jlab.org, lindgren@jlab.org