Difference between revisions of "Mott Run 2 Journal"
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= Pre-Run Beam Setup and Tests (2 shifts) = | = Pre-Run Beam Setup and Tests (2 shifts) = | ||
# Recovery to FC2 @ 6.3 MeV by 10/15 | # Recovery to FC2 @ 6.3 MeV by 10/15 | ||
| − | # Mott beam test - Test 31 MHz synchronization, set L/R/U/D delays, set PMT HV, check PMT response | + | # Mott beam test - Test 31 MHz synchronization, set L/R/U/D delays, set PMT HV, check PMT response, dump dipole degaussed |
# Beam diagnostics - Test harp, BCM calibration, quick emittance method | # Beam diagnostics - Test harp, BCM calibration, quick emittance method | ||
| Line 28: | Line 28: | ||
== 2.0 shifts Sensitivity of analyzing power vs. energy about 5.0 MeV == | == 2.0 shifts Sensitivity of analyzing power vs. energy about 5.0 MeV == | ||
| + | # Imagine 0.5 shift/energy => 4 energies (4.0, 4.5, 5.5, 6.0) | ||
| + | # In 1 hour: set nominal energy, measure precisely, forego emittance measurement but set spot size at target | ||
| + | # In 3 hour: asymmetry measurements at 1.0, 0.75, 0.50, 0.225 um | ||
== 1.0 shifts Repeat spot size and possibly energy spread systematic at KE=5.0 MeV == | == 1.0 shifts Repeat spot size and possibly energy spread systematic at KE=5.0 MeV == | ||
| + | # Use emittance measurement to calculate RMS beam size on foil (minimum, 1.0, 1.5, 2.0 mm) | ||
| + | # Varying energy spread a bit more tricky since energy and to some extent emittance depends on phase in second cavity : maybe a measurement for another time? | ||
== 0.5 shifts Asymmetry vs. beam intensity == | == 0.5 shifts Asymmetry vs. beam intensity == | ||
| + | # Test beam and Mott spectra (TOF + discriminators) up to 100 uA to dump in through hole | ||
| + | # Measure asymmetry 0.35 um foils (1, 5, 10, 25, 50, 75, 100 uA). | ||
Revision as of 07:25, 7 October 2015
Prep and HCO w/o beam
- (John) 31 MHz laser -
- (Riad) Test laser RF trigger at DAQ
- (Joe) Make a photocathode – SL5247-4 (52471-1 was used for Run I, but it's being removed from Gun2 next week)
- (Marcy) Check Mott vacuum, configuration (hipot 3D01 again?)
- (Joe) Cycle target ladder, test camera, test magnets, test 2D harp
- (Riad/Daniel) Check HV, check DAQ, Analysis, Macros ready for 31 MHz
Pre-Run Beam Setup and Tests (2 shifts)
- Recovery to FC2 @ 6.3 MeV by 10/15
- Mott beam test - Test 31 MHz synchronization, set L/R/U/D delays, set PMT HV, check PMT response, dump dipole degaussed
- Beam diagnostics - Test harp, BCM calibration, quick emittance method
Run II Proposed Plan (9 shifts 10/23 DAY - 10/26 OWL)
2.0 shifts - Good knowledge of beam (energy, energy spread, emittance)
- Set KE=5.0 MeV
- Measure emittance at MQJ0L02
- Measure energy spread at IHA2D00
- Verify BCM calibration good
- Calibrate PITA IHWP=in/out
- Setup beam to Mott, check PMT HV, TOF spectra, set thresholds HI, check instrumental asymmetry
- Setup spin direction, use Mott for final adjustment
3.5 shifts Target thickness extrapolation at KE=5.0 MeV
- Use the 10 foils with 25mm aperture spanning 8 nominal thicknesses (0.05, 0.05, 0.225, 0.35, 0.35, 0.50, 0.625, 0.750, 0.87, 1.0)
- Interleave 1um gold foils to demonstrate stabiilty
2.0 shifts Sensitivity of analyzing power vs. energy about 5.0 MeV
- Imagine 0.5 shift/energy => 4 energies (4.0, 4.5, 5.5, 6.0)
- In 1 hour: set nominal energy, measure precisely, forego emittance measurement but set spot size at target
- In 3 hour: asymmetry measurements at 1.0, 0.75, 0.50, 0.225 um
1.0 shifts Repeat spot size and possibly energy spread systematic at KE=5.0 MeV
- Use emittance measurement to calculate RMS beam size on foil (minimum, 1.0, 1.5, 2.0 mm)
- Varying energy spread a bit more tricky since energy and to some extent emittance depends on phase in second cavity : maybe a measurement for another time?
0.5 shifts Asymmetry vs. beam intensity
- Test beam and Mott spectra (TOF + discriminators) up to 100 uA to dump in through hole
- Measure asymmetry 0.35 um foils (1, 5, 10, 25, 50, 75, 100 uA).