CREXAuxiliaryMeasurements-Aug2020

CREX Main << August 2020 CREX Run Plan

Schedule

• This is just a proposal, not settled.

Saturday

• Swing: Pedestal Scan, PITA

Sunday

• Owl: Production
• Day: Optics
• Swing: Optics

Monday

• Owl: Final Q2 measurement. Inelastic Scan. (If time, Poletip study?)
• Day: Beam Studies
• Swing: Beam Studies, Production (with Blind Quartz for check)

Tuesday

• Owl: Production
• Day: Moller measurement. Sign check.
• Swing: Production

Wednesday

• Owl: Production
• Day: Raster and Target study
• Swing: Production

Thursday

• Owl: Production
• Day: DONE

Optics and Q2

1. Energy Measurement (Doug) (non-invasive)
   • I think this is complete. I need to check with Doug.
2. Q2 measurement
   • Repeat of Q2 measurement, with improved pedestal noise control.
   • Detector counting mode.
   • S0 trigger
   • production raster and beam position
3. Optics Data
   • Sieve IN, dp=+1, 0, (maybe -1). Raster/no raster thin C, raster H20
   • See grid on optics data spreadsheet

Backgrounds

1. Blinded Quartz
   • Longish access to setup and back out, but short data taking period (production conditions).
   • Reconfigure AT detectors to use blinding cap, attach to US PMTs.
   • This will be done during the long beam studies break on Monday
   • Integrating measurement for asymmetry measurement
   • Counting mode measurement for rate?
   • Can we make a plan for yield measurement? Maybe use absolute table top gain measurements?
2. Inelastic spectrum scan (~1 shift)
   • Needs a detailed run plan
   • Counting mode. Current 0.5uA or so? Turn quartz HV off.
   • Measure dp spectrum form dp=nominal to dp=-25%, in 5% steps.
   • should scale all spectrometer magnets (including septum)
   • Once the elastic peak is out of the focal plane, it may be possible turn on the S3 and S0 scintillator. This should be done when possible, and the T1/T2/T3 trigger rate recorded for each run.
3. Pole tip re-scattering
   • Requires investigation or planning - do we have an idea here?
   • Q2 or septum mis-tune, to increase interception on pole tip and improve poletip rescattering estimate

Detectors

1. Linearity Studies (PITA + current scans)
   • These are ongoing - should continue regularly. ~ 1 hour every 3 days.
   • Current scans for detector and BCM pedestals
2. Linearity LED tests
   • This will be studied post run, during SAD
   • detector crew were left off the SAD access list - Kent needs to get this fixed.

Other

1. Sign check
   • perform at next Moller polarimeter measurement
   • run Moller, Compton, and parity DAQ for quick PITA scan
2. Target/Raster study

Moller polarimetry

1. One more measurement

Compton polarimetry

1. Flip DOCP???
2. No-target runs
3. Laser polarization optimization
4. Laser polarization flip
5. linearity studies