Difference between revisions of "Run Group C"
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** x-Raster power supply oscillations | ** x-Raster power supply oscillations | ||
* Short Range Plan | * Short Range Plan | ||
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| − | + | ** With to 12C target. | |
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*** Do a current scan to determine the optimum luminosity 1 nA, 2 nA, -> 5 nA if DC occupancies are reasonable. Do separate runs with monitoring histograms in the logbook for each. | *** Do a current scan to determine the optimum luminosity 1 nA, 2 nA, -> 5 nA if DC occupancies are reasonable. Do separate runs with monitoring histograms in the logbook for each. | ||
*** Move the beam around (DC with raster offsets) to study the DC occupancies in all 6 sectors for different raster positions (up to x = +/- 8mm, y = +/- 8 mm). This will allow us to find the best compromise between raster radius and luminosity. Questions? Call expert (EUGENE or Sebastian) | *** Move the beam around (DC with raster offsets) to study the DC occupancies in all 6 sectors for different raster positions (up to x = +/- 8mm, y = +/- 8 mm). This will allow us to find the best compromise between raster radius and luminosity. Questions? Call expert (EUGENE or Sebastian) | ||
Revision as of 08:25, 18 June 2022
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- Shift Documentation
- Phone Numbers
- Short Term Schedule
- Shift Expert
- Worker Shift
- Monitoring
- Useful Links
Shift ScheduleHall B LogbookESAD, COO, RSADShift ChecklistHot CheckoutBeam Time Accounting
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Manuals
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Procedures |
JLab Logbooks
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NOTE: All NON-JLab numbers MUST be dialed with (757) area code. When calling from a CH landline, dial "9" first. To call from outside, all 4-digit numbers must be preceded by 757-269
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- Note, all non-JLab numbers must be dialed with an area code. When calling from a counting-house landline, dial "9" first.
- To call JLab phones from outside the lab, all 4-digit numbers must be preceded by 757-269
- Click Here to edit Phone Numbers. Note, you then also have to edit the current page to force a refresh.
Click Here to edit Phone Numbers. Note, you then also have to edit the current page to force a refresh.
CLAS12 Run Group C, Summer 2022
Daily RC Meetings at 14:00: CH Room 200C, and on Zoom
Zoom information: Link, Meeting ID: 160 867 4253, Passcode: 786506
- Dial "9" before all numbers when calling from CH
Run Group Coordinator: Sebastian Kuhn
- (9-)757 639-6640
RC: Angela Biselli
- (9-)757 575-7540 or
- call the counting house for the personal cell
PDL: Eugene Pasyuk
- (9-)757 876-1789 , x6020 office
Run Coordinator and Target Expert Schedule
Longterm Run Plan
IMPORTANT NOTES:
- If you have symptoms or a positive COVID test, do NOT come to your shift - instead, inform the PDL and the RC immediately so that replacements can be arranged
- If needed, worker shifts can also be taken from off-site - again, inform the PDL and RC. Also, make sure that you follow the instructions under the "Worker Shift" Tab - you need some lead time to set up!
- Before leaving the hall and going to beam permit check that dome lights, forward carriage lights, and pie tower lights are OFF
- NEW: We have a new policy NOT to leave the beam viewer in the beam at all times, to avoid damage to electronics, cameras etc. Please ask MCC to REMOVE the beam viewer unless we are actively tuning the beam or calibrating beam position/raster.
- NEW: We have a new FSD condition that the raster is operating.
- IF there is any ammonia sample (NH3 and ND3) in the target, the raster MUST be operating at all times. The Raster FSD must be UNMASKED. Orbit locks MUST be OFF (except for brief moments to restore beam position).
- For beam tuning or other non-rastered beam, the Raster FSD must be MASKED.
- NOTE: To be safe (from DAQ crashes), quit RasterMon at the end of each run and restart after a successful "Go" for the next run.
- REMINDER FOR ALL EXPERTS: Please take care to fill out the BTA carefully and correctly. The info from EPICS is not always correct, e.g. when taking data with low beam current, you should change the ABU to the proper (estimated) time by hand instead of simply accepting "0" if you are actually taking data.
Known issues:
- ECAL_HV_SEC2_WI_E36 is off as it does not hold voltage
- DC hole in sector 3 remains, would likely need a major physical repair on the chamber itself
Run Plan: June 2022
- ONGOING ISSUES
- Fix FSD Downstream https://logbooks.jlab.org/entry/4003880
- spin dance
- x-Raster power supply oscillations
- Short Range Plan
- With to 12C target.
- Do a current scan to determine the optimum luminosity 1 nA, 2 nA, -> 5 nA if DC occupancies are reasonable. Do separate runs with monitoring histograms in the logbook for each.
- Move the beam around (DC with raster offsets) to study the DC occupancies in all 6 sectors for different raster positions (up to x = +/- 8mm, y = +/- 8 mm). This will allow us to find the best compromise between raster radius and luminosity. Questions? Call expert (EUGENE or Sebastian)
- ASK MCC TO MASK THE RASTER FSD AND MAKE SURE RASTER IS TURNED OFF. Ask for beam to be centered on nominal values for 2C24 and 2H01 - they MAY use orbit locks for that. THEN ASK THEM TO TAKE ORBIT LOCKS OFF AGAIN.
- Set Amplitudes (Vpp) to zero for both horizontal and vertical on Driver
- First run with offsets 0.0 and both Outputs OFF. Start DAQ - the following can be done within a single run
- First enable horizontal driver (Output ON). Then go through the following sequence of offsets: -1 V, -1.2, -1.4, -1.6; +1 V, +1.2, +1.4, +1.6 (max., see below)
- For each offset, send monitoring histograms to logbook, then after going to the next offset, clear all monitoring histograms. Also, for each offset, note (or send to logbook) data rate in CODA GUI. Check the Region 1 occupancies (green histograms with 6 sectors showing occupancies vs. region) for each new offset and stop the sequence above if occupancies go above 7% anywhere. You SHOULD see an increase in the Sector 1 Region 1 occupancies for the NEGATIVE set of offset voltages, and then an increase for Sector 4 for the positive offset voltages.
- Set all offsets back to 0, then turn off the horizontal output and enable the vertical output.
- Repeat the above sequence for the same offset voltages for the vertical. Negative voltages should increase the occupancies in sectors 5 and 6, while positive voltages should mostly affect sectors 2 and 3.
- Set all offset voltages back to 0. The goal is to find at which offsets the occupancies go above 6%. The corresponding voltages in x and y should be MULTIPLIED BY 2 to set Vpp both horizontally and vertically. These will be our final raster size. (The Vpp's shouldn't be too far off the values we had before - 2.8 V in x and 2.4 V in y).
- Test run with full raster (set to amplitude found above).
- DC HV scan (call Florian)
- road validation run (see https://logbooks.jlab.org/entry/4002306 )
- 2 shifts of standard production data taking
- Switch to NH3 and run until Wednesday
- On Wednesday, switch to ND3 target
- Cold-irradiate ND3 target until Thursday (Machine maintenance)
- With to 12C target.
- DURING Machine maintenance day:
- anneal ND3 and try to polarize
- leave with empty target in place
- Once beam is back:
- Take a zero-field run (sub-1 nA) and an empty target run (NO raster) - Contact Rafayel when doing the alignment run and see https://logbooks.jlab.org/entry/4002306 and https://logbooks.jlab.org/entry/4003282
- postponed activities
- Turn raster off and mask raster FSD.
- Take one run with raster off and beam centered on the crosshair
5-pass (10.55 GeV) Running conditions
- Torus at 100% current, inbending electrons. Setpoint +3766 A
- Solenoid setpoint +2417.5 A
- Establish optimal compromise between raster size (if possible, 7 mm radius), luminosity (goal: <5 nA), and background.
- Run duration 100M events or 4 hours, whichever comes first.
- For empty target runs, increase beam current as much as possible (up to 15 nA).
DAQ configuration
- Configuration PROD66_PIN, trigger file rgc_300MeV_v1.0_no_DC.trg
- NOTE: UNLESS a RICH problem crashes the DAQ, do NOT interrupt an otherwise smooth run to do a RICH recovery - instead do this in between runs.
- NOTE: BOTH the shift expert AND the shift worker MUST check and reset monitoring histograms at least once every 30-60 minutes to make sure there are no major detector problems.Watch the raster pattern!
- At the end of each run, follow the STANDARD DAQ RESTART SEQUENCE:
- "end run", if the run ended correctly then: "prestart", "go"
- if the run did not end correctly or if any ROCs had to be rebooted:
- "cancel", "reset"
- "configure", "download", "prestart", "go"
- After each step, make sure it is completed in the Run Control message window. If a ROC has crashed, find which one it is, issue a roc_reboot command ON JUST THAT ROC and try again. Contact the DAQ expert if there are any questions.
References and Standards
Solenoid set-point of 2417.5 A results in read back 2419.57 A and exactly 5.00 T field on center
Nominal Beam Positions
- 2H01, X: -0.35 mm, Y: +0.3 mm (only used/useful without rastering)
- 2C24, X: -2 mm, Y: 0.6 mm (orbit lock)
FSD Thresholds (to be updated)
- Upstream: 2000 Hz
- Midstream: 2000 Hz
- Downstream: 500000 Hz
- BOM: masked. Not used in this run.
- 5 ms dwell time
Reference Harp Scans for Beam on Faraday Cup 2H01 [1]
Reference Harp Scans for Beam on Tagger dump 2C21 [2], tagger harp [3]
Reference Monitoring Histograms
Counter rates
- Upstream counters integrated rates: 0-15 Hz (acceptable up to 100 Hz are acceptable) @50 nA.
- Midstream counters: 10-20 Hz (acceptable up to 50 Hz) @50 nA.
- Counting rates of ~ hundreds of Hz may indicate bad beam tune or bleed-through from other Halls.
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NOTE: BOTH the shift expert AND the shift worker MUST check monitoring histograms at least once every 30 - 60 minutes to make sure there are no major detector problems.
(remote) shift worker: see dedicated Worker Shift tab above. |
For REMOTE Shifts (offsite):
Shift Worker TasksEvery Run:
Every Shift:
Regularly:
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Webcams
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Manuals |
Epics on the web
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Live Monitoring Links |
Hall-B |
Accelerator |
ZOOM meetings
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