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    User name R. Subedi

    Log entry time 22:00:55 on January 16, 2009

    Entry number 256396

    Followups:

    keyword=Run Coordinator Report: Jan 15 (Day)- 16(Day), 2009

    <pre>
    Jan 15 (Thu)-16 (Fri), 2009:
    ---------------------------
    Current polarity status of the spectrometers: BigBite -ve (for electron),
    L-HRS +ve (for Pi-plus).

    Charge Accumulated Summary So Far
    ---------------------------------

    Half Wave Plate Charge Expected (C) Charge
    Accumulated (C) Comment
    Pi-minus Vertical IN 3.5 0.86
    -
    Pi-minus Vertical OUT 3.5 4.04
    Done

    Pi-minus Transverse IN 3.5 0.62
    -
    Pi-minus Transverse OUT 3.5 4.38
    Done

    Pi-plus Vertical IN 3.5 2.24
    -
    Pi-plus Vertical OUT 3.5 3.72
    Done

    Pi-plus Transverse IN 3.5 2.29
    -
    Pi-plus Transverse OUT 3.5 3.66
    Done

    Currently we are in Pi-plus Transverse mode with the half-wave-plate IN.
    We will stay with the
    half-wave-plate IN state until the last of the experiment as the goal of
    the accumulated charge
    in the half-wave-plate OUT state was already achieved.

    Overall Plans
    -------------
    1. Will stay at Pi-plus Transverse mode until Sunday (Jan 18).
    2. Will go to Pi-plus Vertical mode on Sunday Day shift (~10:00).
    3. Will do positron runs on next Thursday (Jan 22) Day/Swing and
    Swing/Owl(Friday) where

    Day/Swing [total one shift]: BigBite +ve polarity and L-HRS +ve
    Swing/Owl [total one shift]: BigBite +ve polarity and L-HRS -ve

    4. Friday (Jan 23) Day: BigBite will be back to -ve polarity, L-HRS stays
    at -ve polarity.

    5. Will do Moller measurement either on next Tuesday or Wednesday.

    Jan 15, 2009 Day-Swing
    ----------------------
    Activities
    ----------

    Day:
    ----
    -Smooth production in Pi-plus Transverse mode
    -Compton photon rate worse: ~2 kHz/uA, after injector tuning it becomes
    better: ~ 300 Hz/uA.
    - RICH-acivity (A. Camsonne et. al.) to understand the high deadtime
    while in RICH-configuration
    will continue until the next Sunday hall-access.
    - Deadtime appears very high or -ve, speculating some of the L-HRS scaler
    channels double-pulsing

    Swing:
    ------
    -Smooth production.
    -4:30 PM: The software that controls the target ladder motion is found to
    be hosted on a
    Hall B web server:
    http://clasweb.jlab.org/medm/HALLA/ha26/HallAGenTarg.edl which is
    inaccessible from Hall A, thus no control for the target motion. After
    contacting
    EPICS expert-on-call it comes back to normal location in half an hour.
    - Target polarization: 65%
    -Datamon code modified: instead of L-HRS scaler, BigBite scalers are used
    to calculate deadtime,
    the deadtime becomes 15%.

    Beamtime Accounting:
    --------------------
    ABU BANU BNA Comment
    Day 6.02 0.75 0.62
    Swing 5:34 1.28 1.38 Reason of BANU: Injector tuning, target
    motion software recovery.

    Jan 16, 2009 Owl-Day
    --------------------

    Activities
    ----------
    Owl:
    ----
    -Smooth production.

    Day:
    ----
    -Smooth production.
    -Compton rate slightly degrades, fluctuates from 200 Hz/uA to 1000 Hz/uA.
    -Gas-cherenkov pedestal becomes wider than usual, planning to take a
    pedestal run to correct it.

    Beamtime Accounting:
    --------------------
    ABU BANU BNA
    Owl 6.71 0.18 1.10
    Day 6:64 0.43 0.92
    </pre>


    A copy of this log entry has been emailed to: transversity@jlab.org