Difference between revisions of "04/01/2020"

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*S.Š:  
 
*S.Š:  
*produced BH plots for [https://halldweb.jlab.org/wiki/images/a/a1/BHe.pdf electrons] and [https://halldweb.jlab.org/wiki/images/b/b4/BHmu.pdf muons], and added them to the proposal (+accompanying paragraph)
+
**produced BH plots for [https://halldweb.jlab.org/wiki/images/a/a1/BHe.pdf electrons] and [https://halldweb.jlab.org/wiki/images/b/b4/BHmu.pdf muons], and added them to the proposal (+accompanying paragraph)
  
 
*MD:
 
*MD:
*Wrote the HDgeant Section in the proposal and added his latest plots.
+
**Wrote the HDgeant Section in the proposal and added his latest plots.
  
 
*AD:  
 
*AD:  
*Revised rates, now accounting for 50% tagger efficiency for lower photon energy, and for the smaller Lorentz  boost at Ebeam=5.5 GeV
+
**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.
+
**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 table Includes a spindance done with GlueX detector. It assumes 8h based on the following:
***0.5% raw asymmetry (half of the 1% physics asymmetry due to PbPt~0.6 and assuming a slight 20% dilution from background)
+
****The asymmetry for hydrogen is 1.7% (4 ub difference and 240 ub sum) including the polarizations gives 1%.
***20kHz of good rate. (We expect 40khz of good rate, but I assumed harsh online cuts so that we stay away from regions where we may have high dilution (forward angles)/poor efficiency).
+
****The asymmetry for deuterium is 2.5% (12 ub difference and 480 ub sum) including the polarizations gives 1.5%.
****5 points at different Wien angles. (we usually do 3 but maybe we should be generous for a first time in Hall D.)
+
****The precision is linear in asymmetry by sqrt of rate. So we need to use the full rate and the diluted asymmetry.
****Each point then takes about 1.4h, for a total of 7h. Then adding a 1h overhead makes 8h.
+
*****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.

Latest revision as of 15:58, 1 April 2020

Present: M.D., A.D., S.Š, J.S.

General:

  • 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.