HAPPEX-Hydrogen E99-115 Shift Plan: Friday, July 9 - Saturday July 10, noon

Updated: July 9, 20:15pm by Dave Armstrong Run Coordinator (pager 584-5411)

Startup Program:

Check HRS magnet and septa current settings
Check that High Voltages for HAPPEX detectors and lumi detectors are on.
Check that the HRS detectors are off (VDCs, etc.)
As soon as CW beam returns:
- Insert BeO target
- Set Raster on
- Ask for 5 µA on BeO target
- Verify raster and beam location on BeO visually
- Verify beam position with 0.3 mm in x,y of (0,0); if not, ask MCC to resteer.
- With spot++, verify the raster size. It should be 3.5x3.5 mm²

Branch Point:

If at this stage it is before midnight or after 4 AM, page Kent and Lisa, and have them come in to set up the helicity-control systems: Hall A and Hall C IA cells, PITA voltages, RHWP.

If it is between midnight and 4 AM, proceed as below:

Move hydrogen target in to beam (loop 2, 20 cm racetrack cell)
Ensure 60 Hz fan speed.
Make sure Fast Feedback is on (MCC)
Ask for 20 µA on target, with raster on.
Check that target is OK
Start HAPPEX DAQ run (not yet production running)
Watch Septa temperatures. Record equilibrium beam-on values (may take 20 minutes to settle)
Meanwhile:
- Look through Panguin plots - verify detectors, lumis, BPMs, BCMs... Lumi's and detectors all should be at around 30 K channels.
- turn on beam modulation (dithering). Verify that typical plot produced.
- take profile scanner run; verify that the profiles are close to the standard.
Calculate "safe" running beam current (such that max. septum coil temps are less than 7.75 K)
end run, ask for beam current at the maximum safe current.
Start new HAPPEX DAQ run
Verify septa temps. are stabilized; don't allow them to exceed 7.75 K! Turn beam current down if needed. Record septa. stable temps and beam current.
Try to make Compton measurement. Expected value with this gun is around 76%.

Production settings

35 µA (or more, if septa allow), raster 3.5x3.5mm², BPMB (x,y) = (0,0) +/- 300 µm, BPMA match to BPMB within 300 µm
Target: Liq H₂, fan speed = 60Hz
Left p0 = 2.9710 GeV/c, I_septum = 275.25 A (feel free to check the math) (setpoint=275.50 A)
Right p0 = 2.9600 GeV/c, I_septum = 274.25 A (setpoint=274.25 A)
Spectrometer detectors OFF
HV on Lumi and HAPPEx detectors should give signals at ~50k ADC channels. Record any changes in HV

Tasks

Every run:
1. Analyze the run. As apar:
```
gopan; prompt.pl 
runnumber
```
2. Check the Hall C beam charge-asymmetry, and correct for if necessary (instructions found in halog entries 126343 and 126460).
3. Add run to the shift runlist (~apar/ShiftyRunlist)
4. If a run is GOOD, add it to shift sluglist (~apar/ShiftySluglist)
Compton (check at least every Happex run)Stop/Start the Compton for every half-wave plate change, and every spot-move. The compton strip-chart should be running: check rates from E- and G-detectors, and that the cavity-power has two levels (left/right helicity photon). Beam position at the Compton should be checked. Instructions for the simple "normal" running and fixes are listed next to the computer.
Every 4 hours of production dataChange the status of the half-wave plate.
Once a shift (when Profiler/Scanner expert is on shift) take a goodprofile run (10min). The beam should not trip off.

General Tasks:

HALOG any detector, DAQ trip and unusual observation when they happen.
Do shift checklist.
Twice a shift HALOG control screens and septum & energy spread strip charts.
Any problem that prevents data taking and that you cannot solve within 30 min page the Run-Coordinator.
During night and weekend shifts contact the Run-Coordinator before the Tech on-call. Any problems that are not emergencies, please make a HALOG entry with "TECH" in the keyword.

Please log below (and in the HALOG) any unusual observations and problems solved

Date/Time Name Comment HALOG

User name Armstrong