Difference between revisions of "04/01/2020"
From GlueXWiki
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**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. | + | ***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%. |
− | ****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. |
Latest revision as of 15:58, 1 April 2020
Present: M.D., A.D., S.Š, J.S.
General:
- S.Š:
- 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.
- The table Includes a spindance done with GlueX detector. It assumes 8h based on the following: