Notes from Meeting May 08, 2009

• Compton DAQ

  • There was a discussion regarding 20 mHz clock in FADC.
    • Scalers seeded in the original DAQ gave errors.
    • Need to figure out it is the clock/scalers which effects the accumulator mode.
    • Bob suggests having second clock to cross check.

• HAPPEX-III Detector

  • Dustin is working with Anatoly in EEL building. Detectors checked out to be Ok.
  • Taking data with cosmics. Detector voltage (HV) is too low, data didn’t look good.

• Møller

  • Luis is working on a set of Møller simulations (green monster, penguin).
  • Bob said we have to finish the green monster before June 15.

• Simulations

  • Talked about Dustin's HAPLOG post 1601.
    • Investigating new PREx optics tune for 8.6% Be plug events according to LeRose’s code, checking signal to background etc.
    • Applied ± 4 MeV events cut and found events converge at (0,0), found the region where there is no noise.
  • Talked about Dustin's HAPLOG post 1602 & 1603.
    • Turned multiple scattering OFF and found out background free regions are from multiple scattering events.
    • Questions remain why multiple scattering widens the peak distribution in x but not in y. KK asks to check the model and understand the asymmetry in the distribution.
    • Examined the A_T hole events using “standard” HRS optics tune with multiple scattering.
    • Found a difference between PREx HRS optics tune and “standard” HRS optics tune when the ±4 MeV cut is applied to the y distribution.
    • There was a conclusion which says the A_T hole measurement may not work using the "standard" HRS optics tune.
    • Bob suggests making a very small detector or align the detector in mm level once the experiment starts.
    • KK suggests to simulate both A_T hole positions and careful checking of Q1, Q2, Q3 positions in the simulations. Q2, Q3 scan need to be done before the experiment.

• Green Cavity

  • Cavity mirrors were contaminated in the vacuum which caused the power loss in the cavity.
  • Recovered the power by cleaning the mirrors.
  • Cleaned the cavity vacuum chamber to prevent further contamination in the future.
  • Cavity exit line power calibration is complete and ready to finish the cavity characterization next week.
  • Kent promised to show Abdurahim how to estimate the power coupled to the non fundamental cavity mode.

comments to: Abdurahim Rakhman