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Logistic information

Meeting room at JLab: REMOTE ONLY

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  1. Dithering update - Ye DocDB:436
    • KP: width of BPM subtraction may be close to BPM resolution. KK: And it introduces systematic in regression.
    • PS: we need different combinations to understand correlation in X (slug ~110).
    • KK: for PREX, we need to look at correlation between energy and position as well
  2. PREX / CREX Respins - Cameron
    • KP: we need data quality check with higher burp cut level. Dave A: It is on-going
  3. Tao : update on block level and polarity averages.HAPLOG 4092
    • KP: blocks level study is indepedent from polarity averages
    • KP: 4 peaks effect is time dependent effect in Pockel cell. We have feedback control so that 4-blocks average is small
    • KP: we can check in the main detectors how well charge asymmetry correction is done with transition differences .

PREX Respin 2, CREX Respin 1

We are close to ready for another round of respins. For these the changes are as follows:

  1. Burp cut changes:
    • Loosen the burp cut so that the modulation data does not trip the burp cut
    • Increase the BPM cut from 0.35 mm to 0.6mm and that seems to rescue the BMOD data from cutting with minimal harm
    • A presentation on this can be made soon by either Quinn, Victoria, or Cameron
    • Unclear if this is needed for CREX yet
  2. Change in the normalizing BCM:
    • The combination "(2*bcm_an_us + bcm_an_ds)/3" will be used for the normalizing BCM, except for runs 3594-3753 which will use bcm_dg_ds
  3. Pedestal updates:
    • Pedestals for BCM vs. unser, and everything vs. that BCM have been obtained for PREX and CREX
  4. Use of combined BPM 11 & 12 in both regression and dithering for PREX, 1X instead of 4aX for CREX
  5. AT detectors added to global error flag:
    • Doing this would allow our normal dithering and regression analysis to work for the ATs in all runs
    • Devi has looked at this, and including them for all two-arm runs would just result in losing 13155 total multiplet patterns from our grand statistics which is ~1.5 miniruns
  6. Include Transverse running data and all NeedCut and Suspicious runs in the respin

Analysis projects

  1. BCM double difference study
  2. BPM resolution
  3. Pedestal / Normalization BCM history
  4. Events/ Patterns Counter
  5. Dithering sensitivity/Quality re-check
  6. Grand statistics re-check
  7. Linearity check


Kent P, Adam Z, Amali P, Brian Q, Cameron C, Carrington M, Caryn P, Chandan G, Ciprian G, David A, Devi A, Devika B, Dmitrii N, Dustin M, Eric K, Hanjie L, Iris H, Juan Carlos C, Juliette M, Krishna K, Paul S, Robert M, Robert R, Ryan R, Silviu C, Siyu J, Victoria O, Weibin Z, Ye T, Guido U


Paul K