Template:ShortTermSchedule-RGK
Experiment Coordinator: Annalisa D'Angelo
Run Coordinator: Daniel Carman (757) 575-7540
PDL: Daniel Carman (757) 876-1789
Important Notes
Do NOT change FSD settings without approval from RC or beamline expert!
In case of medical or fire emergency, call 9-911 from a LANDLINE phone in the Counting House and inform the Crew Chief and RC.
In case of evacuation of the Counting Room (e.g., due to a fire alarm), grab the shift expert phone and leave the room through the "EXIT" door leading to the parking lot. Do not leave through the hallway! Call the RC once outside so the latter will call MCC to turn the beam OFF to Hall B and inform other Hall B staff members.
If you have symptoms or a positive COVID test, do NOT come to your shift - instead, inform the PDL and the RC and JLab medical services immediately to arrange replacements.
Remote shift: If needed, worker shifts can be taken from off-site. Inform the PDL and RC. Also, make sure that you follow the instructions under the "Shift Worker" tab, as you need some lead time to set up!
Note to Shift Takers:
- Read the ESAD, COO, RSAD, and ERG documents found on the "Current RG-K Run Info" as well as the yellow folder in the counting room. Before you start your first shift on the current experiment, you must sign on the list in the yellow folder. Thereby, you confirm that you have read and understand their content.
- Read at least the previous 24 hours logbook entries to be aware of recent run details and changes
- Arrive at least 10 minutes early for shift change
- If it is your first shift or a shift after a long pause, do shadow an earlier shift for at least 4 hours to familiarize yourself with all shift duties and technicalities of the ongoing experiment.
- Refresh the run wiki page/tabs; look over it/them every shift
- Follow the Shift Expert/Worker tab's instructions
- Do not spend more than 15-20 min trying to fix a problem. In case of any issue, contact the On-call Experts or the RC.
See tab GENERAL INFORMATION for
- Recent Changes
- Current Issues
- Beam Restoration (for beam restoration procedures and Møller runs)
Run Plan: Feb. 28 - Mar. 4, 2024
Beam Restore
1) About 90 minutes before beam is ready for delivery: Energize tagger magnet and prepare for beam delivery to tagger yoke dump (blank collimator, beam type photon, CLAS12 detectors off (BMT HV in safe mode)) 2) Follow instructions to tune beam to tagger dump yoke (contact Eugene for questions); Compare 2C21A and 2C24A harp scans to reference 3) Take two Møller runs at 20 nA with HWP out (Helmholtz polarity negative and positive) (contact Nathan for questions) 4) Call MCC to change HWP to in (coordinate with Hall C beforehand!); after transition contact Hall C to run flipper script; check charge asymmetry (contact Eugene if it is outside tolerance) 5) Take two Møller runs at 20 nA with HWP in (Helmholtz polarity negative and positive) 6) Turn beam off and degauss tagger magnet (20 mm collimator, beam type electron) 7) Follow instructions to tune beam to the Faraday cup (contact Eugene for questions); Compare 2H01 harp scan to reference 8) When the tune is acceptable (halo monitors and beam positions at 2C21A, 2C24A, 2H01), turn all CLAS12 detectors on 9) Increase beam up to 75 nA (checking halo rates and beam positions at 25 nA and 50 nA)
Production Running
- DAQ configuration: PROD67, Trigger: rgk_noDC_v1.1_300MeV.trg - Beam current request: 75 nA (at 2C21A) - Run duration: 3 hrs - Take production data until Rafo is available for beam blocker calibration (~8 a.m.)
Empty Target Running
- Turn beam off and empty LH2 target - Complete beam blocker calibration (Rafo will lead effort, duration 2 hrs). Note: Beam blocker must be installed for running more than 5 minutes above 100 nA - When beam blocker calibration is finished, install beam blocker. Request 200 nA to the FC and begin DAQ for empty target running. Take 3 hr runs until charge collection is 10 mC (10-12 hrs of good beam)
Luminosity Scan
- Fill target (duration 30 min) - Take production data at beam currents of 5 nA, 30 nA, 50 nA (using triggers given below) - Run duration: 10M triggers for each beam current - 5 nA DAQ configuration: PROD67, Trigger: rgk_5na_noDC_v1.1_300MeV.trg - 30 nA DAQ configuration: PROD67, Trigger: rgk_30na_noDC_v1.1_300MeV.trg - 50 nA DAQ configuration: PROD67, Trigger: rgk_45na_noDC_v1.1_300MeV.trg
Production Running
- DAQ configuration: PROD67, Trigger: rgk_noDC_v1.1_300MeV.trg - Beam current request: 75 nA (at 2C21A) - Run duration: 3 hrs
Related Information
Find detailed information at tab "GENERAL INFORMATION".
- The main lights in the Hall (dome lights) and the Forward Carriage lights must be OFF during run time.
- Orbit locks are on BPMs 2C24A and 2H01 and the locks should generally be on ("Running").
- Beam positions at 2C24A and 2H01 have to be kept, within ±0.1mm, at the nominal beam positions listed below ("Reference Values").
- The beam position at 2C21A is not important for production runs but should be stable. Here, significantly drifting positions can indicate instabilities in beam energy.
- The beam position at 2C21A is important for initial beam tuning (on tagger dump).
- If HWP is changed, start a new run. The absolute values of the SLM and FCUP charge asymmetry (Q-Asym (%)) should be less than 0.1%.
- Beam tuning and Møller runs
- Generally, Detector HV OFF but
- SVT: LV ON; HV OFF, and MVT: LV ON; HV ON - Safe Voltage
- Turn DC HV off only for beam tuning
Access to the Hall
- If you need to enter Hall B, alert Denny Insley (757-897-9060, cell/text: 757-810-9576) and the Run Coordinator (757-575-7540).
- Check in with the shift personnel before entering the hall.
DAQ Operation & Related Information
NEW STANDARD end and start of the run:
This will ensure proper compression of the FADCs and therefore a smaller data rate and perform a RICH recovery. Restart DAQ
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Triggers files
rgk_noDC_v1.0_300MeV.trg | DC roads are not in the trigger. Hold off time is 3 us. |
rgk_noDC_v1.1_300MeV.trg | DC roads are not in the trigger. Hold off time is 2 us. |
rgk_noDC_v1.2_300MeV.trg | DC roads are not in the trigger. Hold off time is 1 us. |
rgk_out_v1.1_300MeV.trg | Outbending DC roads, Hold off time is 2 us. |
Reference Values
FSD Thresholds
- Upstream: 2 kHz
- Midstream: 2 kHz
- Downstream: 100 kHz
- BOM: 50 kHz
- 5 ms dwell time
Nominal Beam Positions
2C21A (not important for production)
- x = -0.4 mm
- y = +0.7 mm
2C24A
- x = -1.7 mm
- y = +0.5 mm
2H01
- x = -0.7 mm
- y = +0.6 mm
8.5 GeV Harp Scan References (Feb. 14, 2024)
2C21A: https://logbooks.jlab.org/entry/4252495
Tagger (2C24A): https://logbooks.jlab.org/entry/4252496
2H01: https://logbooks.jlab.org/entry/4252514
6.4 GeV Harp Scan References (Jan. 18, 2024)
2C21A: https://logbooks.jlab.org/entry/4240375
Tagger (2C24A): https://logbooks.jlab.org/entry/4240378