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    User name R. Subedi

    Log entry time 11:07:52 on January22,2009

    Entry number 257292

    Followups:

    keyword=Run Coordinator Report: Jan 21, 2009


    Run Coordinator Report for Jan 21, 2009:
    # Polarity status of the spectrometers: BigBite -ve (for e-), L-HRS +ve (for &pi+)
    # &pi+Vertical mode with the half-wave-plate IN
    Charge Accumulated Summary So Far

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

    &pi-Transverse IN 3.5 0.62 -
    &pi- Transverse OUT 3.5 4.38 Done

    &pi+ Vertical IN 3.5 4.90 Currently here
    &pi+ Vertical OUT 3.5 3.72 Done

    &pi+ Transverse IN 3.5 4.5 Done
    &pi+ Transverse OUT 3.5 3.66 Done

    Overall Plans
    1. Will do Moller measurement on Jan 22, 7 PM.
    2. Will do positron runs on Thursday (Jan 22) Day/Swing and Swing/Owl(Friday) where

    Day/Swing [starting 07:00]: BigBite +ve polarity and L-HRS +ve
    Swing/Owl [starting 17:00]: BigBite +ve polarity and L-HRS -ve

    3. Friday 07:30: BigBite will be back to -ve polarity, L-HRS stays at -ve polarity.
    4. Will stay for about a week of production in &pi-Vertical mode.

    Activities
    - The frequent BigBite HV (BB HV) trips becomes less frequent when asked to ramp up the
    beam current slowly after a beam trip, this may be just a coincidence.
    - 12:15- 15:22 MCC tuning the beam through ARC4 magnet which was causing all the BB HV trips.
    - 15:40 Checking beam with BeO and doing spot++ with different raster sizes,
    and starts production. Not many HV trips now.
    - In the Swing another accelerator magnet (MQA9A23) shows mismatch causing a beam mis-tuning.
    This mis-tuning also causes BB HV trips. After tuning through MQA9A23, BB HV trip
    gets minimized (just ONE trip during the Owl of Jan 22).
    - Production on polarized 3He in &pi-Vertical mode.

    Beamtime Accounting:
    ABU BANU BNA Comment
    Owl 6.99 0.44 0.56
    Day 3036 1.12 3.51 3 hrs of Beam tuning through ARC4 magnet
    Swing 6.59 0.27 1.13 Beam tuning through the accelerator magnet MQA9A23