Difference between revisions of "Run1 - January 2015"

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This page will be used for the Run 1 experiment and analysis
 
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= Shift Schedule =
 
= Shift Schedule =
 
[[File:140112_shifts.png|thumb|center|300px]]
 
[[File:140112_shifts.png|thumb|center|300px]]
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#Measure energy spread
 
#Measure energy spread
 
#Calibrate BCM to FC2
 
#Calibrate BCM to FC2
 +
 +
= Mott Setup and Systematics Testing (Sat Jan 17) =
 +
#Setup good orbit to Mott
 +
#Set PMT HV
 +
#Set PMT energy thresholds
 +
#Set polarization vertically
 +
#Calibrate PITA vs IHWP IN/OUT
 +
#Finalize orbit w/ instrumental asymmetry, TOF and spectra
 +
#Adjust target offsets per vertical instrumental asymmetry
 +
#Measure dump rate fraction to determine run times
 +
#Measure dead-time vs. rate
 +
#Measure asymmetry vs. beam current
 +
#Measure asymmetry vs. time (stability)
 +
#Measure asymmetry vs. spot size
 +
#Measure asymmetry vs. energy spread
 +
 +
= Target Foil Extrapolation (Sat Jan 17 - Mon Jan 19) =
 +
: 14 foils to study + 1 thru hole
 +
spectra – with typical low ~2 MeV energy threshold
 +
statistics – possibly higher ~3 MeV threshold to reduce dump events
 +
:Deadtime
 +
Semi-int mode we use w/ FADC/TDC/scalar is ~5% @ 1500 Hz
 +
: Inelastic fraction
 +
Worst case ~200 Hz/det  (best case ~25 Hz/det)
 +
Energy threshold will be defined to set this value
 +
Time veto is tricky and too risky at 62 MHz
 +
: Assuming I=5uA, R<1500Hz, 200Hz/det background
 +
28 hours * 1.2 / 8 = 4-5 shifts
 +
dP/P sets N_elastic (using 1σ analysis cut of all 4 det)
 +
Measurement of of inelastic (dump) events figures into run time
 +
: [[File:140112_runtimes.png|thumb|center|300px]]

Revision as of 14:54, 12 January 2015

Shift Schedule

140112 shifts.png

Shift Worker Duties

Beam Driver
Beam setup: gun + laser + spin + beam to Mott
BCM & target motion FSDs enabled 
Vacuum levels reasonable
Magnet and RF setup saved
PITA adjusted for IHWP IN/OUT
DAQ Driver
Start/Stop DAQ entering correct run information
Monitor event rates and maintain dead time <5%
Coordinate run start/stop with Beam and Analysis Drivers
Analysis Driver
Runs decoded, analyzed and promptly inspected
Run # and information logged onto run sheets
Elastic events counted for IHWP=IN/OUT

Prep Work (through Tuesday Jan 13)

  1. Make a photocathode – SL5247-1 made
  2. Test IHA2D00 – wires & stroke good, but data file odd vs. others
  3. Hi-Pot IP – FE’r potted, but high again, vac readback not good
  4. CHL 2K cooldown – maybe early, Monday Jan 12th
  5. Install laser – Tue or Wed
  6. Test laser RF trigger – after laser installed (1V, 10ns @ RF)
  7. Verify beam line layout –documented below
  8. Build elegant deck – working
  9. Build qsUtility config file –documented below

Injector Setup and Mott Checkout (Wed Jan 14 - Fri Jan 16)

  1. Restore beam to FC2 @ 6.3 MeV/c
  2. Mott test: DAQ FADC/TDC synchronization
  3. Mott test: event separation and transmission at 62MHz acceptable
  4. Quad center BPMs for momentum measurement
  5. Test harp IHA2D00 if ready for energy spread measurement
  6. Scale cryounit for p=5.487 MeV/c and minimize energy spread
  7. Precisely measure beam momentum
  8. Measure beam emittance
  9. Measure energy spread
  10. Calibrate BCM to FC2

Mott Setup and Systematics Testing (Sat Jan 17)

  1. Setup good orbit to Mott
  2. Set PMT HV
  3. Set PMT energy thresholds
  4. Set polarization vertically
  5. Calibrate PITA vs IHWP IN/OUT
  6. Finalize orbit w/ instrumental asymmetry, TOF and spectra
  7. Adjust target offsets per vertical instrumental asymmetry
  8. Measure dump rate fraction to determine run times
  9. Measure dead-time vs. rate
  10. Measure asymmetry vs. beam current
  11. Measure asymmetry vs. time (stability)
  12. Measure asymmetry vs. spot size
  13. Measure asymmetry vs. energy spread

Target Foil Extrapolation (Sat Jan 17 - Mon Jan 19)

14 foils to study + 1 thru hole
spectra – with typical low ~2 MeV energy threshold
statistics – possibly higher ~3 MeV threshold to reduce dump events
Deadtime
Semi-int mode we use w/ FADC/TDC/scalar is ~5% @ 1500 Hz
Inelastic fraction
Worst case ~200 Hz/det  (best case ~25 Hz/det) 
Energy threshold will be defined to set this value
Time veto is tricky and too risky at 62 MHz
Assuming I=5uA, R<1500Hz, 200Hz/det background
28 hours * 1.2 / 8 = 4-5 shifts
dP/P sets N_elastic (using 1σ analysis cut of all 4 det)
Measurement of of inelastic (dump) events figures into run time
140112 runtimes.png
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