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Present: M.D., A.D., S.Š, J.S.


  • S.Š:
    • produced BH plots for electrons and muons, and added them to the proposal (+accompanying paragraph)
  • MD:
    • Wrote the HDgeant Section in the proposal and added his latest plots.
  • AD:
    • Revised rates, now accounting for 50% tagger efficiency for lower photon energy, and for the smaller Lorentz boost at Ebeam=5.5 GeV
    • Added a section table of beam time request/timeline summary.
      • The table Includes a spindance done with GlueX detector. It assumes 8h based on the following:
        • The asymmetry for hydrogen is 1.7% (4 ub difference and 240 ub sum) including the polarizations gives 1%.
        • The asymmetry for deuterium is 2.5% (12 ub difference and 480 ub sum) including the polarizations gives 1.5%.
        • The precision is linear in asymmetry by sqrt of rate. So we need to use the full rate and the diluted asymmetry.
          • For hydrogen this is 40kHz and 1%*10/74 = 0.14%.
          • For deuterium the is 44kHz and 1.5%*20/84 = 0.36%
        • To get a 2% uncertainty it takes 9.5 hours and for deuterium 1.2 hours. (So, a spin dance is practical only using deuterium. )
        • Assuming we do it on the D and we do 5 points, then it takes 7h. We can assume 1h of overhead for wien angle change and stop/start runs.