Pol He3 Target Meeting May 4, 2020
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Revision as of 15:11, 4 May 2020 by Mrehfuss (Talk | contribs) (Created page with "Begin time: 1:30 p.m. End time: 2:40 p.m. Members present: Jian-ping, Todd, Brad, Mingyu, Melanie, Junhao, Xiaochao, Arun, Bill, and Christopher Jantzi Mingyu * Building on...")
Begin time: 1:30 p.m. End time: 2:40 p.m.
Members present: Jian-ping, Todd, Brad, Mingyu, Melanie, Junhao, Xiaochao, Arun, Bill, and Christopher Jantzi
Mingyu
- Building on polarimetry runlist
- want to learn how the beam current affects the target polarizations (depolarization)
- use (total charge/beam on time) to calculate the average current per run
- the average current is located in the report file, but won’t be the most useful for us since the average current uses beam-off time (which can be a significant amount of time)
- Brad: FYI: Mya (EPICS archiver) records the beam current at all times. Can do time correlations to look at region of interest. Info is also stored in CODA files for run-by-run information
- want to learn how the beam current affects the target polarizations (depolarization)
- Need to find out the target tests done (polarization loss, temperature tests, etc.) on Feb. 10th before Dutch was swapped out for Big Brother
Melanie
- Show explicitly how the errors were calculated in the frequency fits in the EPR analyses
- been using the midpoint in the event of a non-straight line (usually due to field instability, which is the biggest systematic affect). this might not be the best way to go – instead implement some correlation between how much each fit deviates from each other
- NMR signal fit was different in January on Dutch – use Junhao’s treatment of the NMR signal instead of the latest fit for the calibrations
Murchhana
- Used a "tiled" and "non-tilted" line to fit Compass data instead of the previously-used ellipse to calculate the uncertainties
- non-tilted produced a +/- 0.02 degree contribution
- tilted fit produced a +/- 0.06 degree contribution
- Since the tilted fit has the lower chai-squared value, perhaps use this fit (although there is reason to believe no x-y correlation should be present...but the error contribution is similar enough to one another that it shouldn't matter much)
Xiaochao says Jixie claims to have ~ 75% of his report on the field measurements completed
Next week, we expect presentations from Junhao and Melanie
