Run Group B
In case of a problem with superconducting magnets call Engineering on-call first, particularly if it is related to cryo.
CLAS12 Run Group B, spring 2019
Beam energy 10.6 GeV (5 pass)
Important: Document all your work in the logbook!
Remember to fill in the run list at the beginning and end of each run (email@example.com can fill the run list)
RC: Silvia Niccolai
- (757) 575-7540
- 9 575 7540 from Counting Room
PDL: Maurizio Ungaro
- (757) 876-1789
- 9 876-1789 from Counting Room
Initial Run Plan:
(last update 2/5/2019- 4:00 PM)
Target should be EMPTY.
Restore beam to the hall, first to the tagger dump, following the procedures described in .
Check beam quality using harp scans 2C21 and 2C24, and compare to old scans.
When the beam quality is acceptable, take a Moeller run to verify polarization, following procedures  If the polarization is acceptable (>=85%), send beam back to Faraday cup, according to the procedure . If not, a spin-dance may be necessary to find the Wien angle maximizing our polarization. If this cannot be done over the weekend, and the polarization is only slightly below 85%, this can be postpone to Monday.
Once the beam is sent to Faraday cup, check the beam quality using the 2H01 harp scan.
Check the alignment of beam with respect to the target and CLAS12, according to the procedures in .
Turn all detectors ON.
Fill up the target with LD2. The procedure is written in the papers which ison the left of the keyboard of the target computer, which is facing the window looking over the electronics room.
At low beam current (~5 nA), check the beam position by looking at the rates on the FTCal. Ideally, if the target and FT are aligned, the rates should be symmetric around the hole. Check DC occupancies.
Data taking, during the weekend: DAQ configuration PROD66, trigger file rgb_v0.trg. Do a current scan (5, 10, 20, 40 nA) checking and writing down trigger rates, data rates, and DC occupancies. Be aware that with a deuterium target we may get higher rates than for RGA, at a given current. Pick the maximum current that allows acceptable rates (DC occupancies ~3-4%, trigger rates~10k, data rates~450 MB/s).
Trigger validation studies, from Monday onwards: Valery and Rafo should be called, and the studies should take about one shift.
- Note 1: Be very mindful of the background rates in the halo counters, rates in the detectors, and currents in the SVT for all settings to ensure that they are at safe levels.
The integrated rates on the upstream counters have to be in the range 0-15 Hz (rates up 100 Hz are acceptable) and the rates on the midstream counters have to be in the range 10-20 Hz (acceptable up to 50 Hz) @50 nA. Counting rates in the range of hundreds of Hz may indicate bad beam tune or bleed-through from other Halls.
- Note 2: At the end of each run, follow the standard DAQ restart sequence
"end run", "cancel", "reset", then if the run ended correctly, "download", "prestart", "go". If the run did not end correctly or if any ROCs had to be rebooted, "configure", "download", "prestart", "go".
After each step, make sure it is complete in the Run Control message window. If a ROC has crashed, find which one it is and issue a roc_reboot command and try again. Contact the DAQ expert if there are any questions.
- Note 3: Nominal beam positions: 2C24A (X=0.2 mm, Y=0.2 mm) , 2H01 (X=0.3 mm, Y=-0.9 mm)
- Note 4: Do not turn OFF FTOF HVs, even during the beam tune with CW beam (turn off when doing a Moller run or if there is tuned/pulsed beam in the upstream beamline)
- Note 5: In case of a Torus and/or Solenoid Fast Dump do the following:
- Notify MCC to request beam OFF and to drop Hall B status to Power Permit
- Call Engineering on-call
- Make separate log entry with copies to HBTORUS and HBSOLENOID logbooks. In the "Notify" field add Ruben Fair, Probir Goshal, Dave Kashy and firstname.lastname@example.org
- Notify Run Coordinator
- Turn off all detectors
- Note 6: When beam is being delivered to the Faraday Cup:
- the Fast Shut Down elements: Upstream, Midstream, Downstream, BOM, and Solenoid should always be in the state UNMASKED
- No changes to the FSD threshold should be made without RC or beamline expert approval
- Note 7: Any request for a special run or change of configuration has to be approved by the RC & documented
- Note 8: Carefully check the BTA every hour and run the script btaGet.py to print for you what HAS TO BE in BTA for this hour. Edit BTA if it is incorrect.
- Note 9: Reset CLAS12MON frequently to avoid histogram saturation.
- Note 10: Shift workers must check the occupancies! Use this tool to compare to previous runs: https://clas12mon.jlab.org/mon12/histograms/
- Note 11 Do not Turn OFF MVT HV: Instead go to 'Restore settings' from the MVT overview screen:
- SafeMode.snp for beam tuning and Moeller runs
- MV_HV_FullField.snp for full solenoid field
- MV_HV_MidField.snp wgeb solenoid < 4T
- NOTE 12 Check the vacuum periodically, make sure vacuum id not higher than 5e-5
- NOTE 13 Always reset the CFD threshold after all power off/on on the CND CAMAC crate
After the CAMAC crate (camac1) holding the CND CFD boards is switched off for any reason, it is mandatory to reset the associated thresholds typing the following command from any clon machine terminal: $CODA/src/rol/Linux_x86_64/bin/cnd_cfd_thresh -w 0
If this command is failing and the crate is not responding, reboot it as follows: roc_reboot camac1
- NOTE 14 Shift workers should anyway check routinely scalers to verify they update correctly and make a logbook entry if anomalies are observed after starting a new run.
- NOTE 15: To solve common SVT issues see https://logbooks.jlab.org/entry/3615766