Run Group C
- Shift Documentation
- Phone Numbers
- Short Term Schedule
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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
Run Coordinator: Larry Weinstein
- (9-)757 575-7540
PDL: Eugene Pasyuk
- (9-)757 876-1789 , x6020 office
Run Group Coordinator: Sebastian Kuhn
- (9-)757 639-6640
Run Coordinator and Target Expert Schedule
Longterm Run Plan
IMPORTANT NOTES:
- In case of medical or fire emergency, call 9-911 from a LANDLINE phone in the Counting House
- 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 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 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: It should no longer be necessary to quit RasterMon at the end of each run and restart after a successful "Go" for the next run, but if DAQ crashes, you SHOULD follow these steps, and the same for mon12. Make sure there is ONLY ONE INSTANCE of RasterMon AND mon12 running anywhere in the Counting House.
- 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.
Run Plan: September 2022
GENERAL INFORMATION
- We should change the HWP ("lambda/2 plate"), after a full day of useful data on NH3 or ND3. WE MUST INFORM THE OTHER HALLS WHENEVER WE DO THAT
- We should reverse the target polarization after every TWO days of good data taking. So the sequence is "1 day on ammonia, swap HWP, one day on ammonia, flip target polarization, one day on ammonia, swap HWP, one day on ammonia". NH3 may have to be annealed between target polarization changes.
- Moller runs should be taken with 10 nA.
- Do a RICH Recovery procedure only once a day during day shift (in between runs) if everything is okay. If a RICH problem occurs, you might have to do the RICH Recovery procedure also (see below).
- After each change of running conditions (target type, luminosity): Please check that the trigger alarms (on rate/nA) are set appropriately and change them as needed.
ONGOING ISSUES
- x-Raster power supply oscillations - Krister is working on it with Danfysik engineer
SHORT RANGE PLAN
Note: Alternate between PROD66 and PROD66_PIN until further notice. PROD66_PIN should have at least 20 M events, otherwise use PROD66_PIN also the following run.
Start-up after Configuration Change (likely Saturday, 9/3)
- First target: 2 cm diameter C target (+ LHe)
- Once beam is available, tune it on the tagger dump.
- Once upstream harp scans are acceptable (see below References and Standards), take a Moller run before degaussing the tagger. (Check for bleedthrough)
- Establish 5 nA beam on the FC. ** Get clean beam **. Raster off/Raster FSD masked.
- Do a harp scan at 2H01.
- Once beam profile and position is acceptable, we need to find the limits in beam position with acceptable DC occupancy. Turn on all detectors, start DAQ and mon12. Notify target group that we will change targets in about 2 hours.
- Get 5 nA beam:
- Ask MCC to move beam in steps of 1 mm in +x-direction until you see a sharp increase in DC occupancies (mon12), especially in Region 1, Sector 4. (Stay below 8% occupancy in R1).
- new method (from EP): look at DC_occupancy_norm and compare the R1 s1 and s4 occupancies. log it for each value of x. choose the position where the s1 and s4 occupancies are equal and small, in between where the rates increase a lot.
- Repeat with -x (watch R1 S1).
- Center beam between the 2 limits found above. Repeat same procedure by moving beam in +y direction (Sectors 2 and 3) and -y direction (Sectors 5 and 6).
- Have MCC center the beam between all limits: this will be our new reference beam position. Record all BPM x and y values and convey to MCC.
- Next step is to check with raster turned on: Offset (0,0) and Vpp(V) = 0.2*Delta-x(mm) , 0.19*Delta-y where Delta-x/Delta-y are the differences in the extreme positions in x and y found above. Take a short run and check mon12 for the occupancy vs. x and y as well as rastermon.
- Decrease beam current to ~2.5 nA
- Increase raster size until you see a 1/2-circle of target walls on rastermon. Then reduce it
- call Sebastian and/or Eugene to determine optimal raster size
- It was too late to call Chris Keith to change targets (LW: 9/3 21:25). Continue C running
- 4th target: continue C with LHe
- Take a series of runs for luminosity scan: 2, 4, 6, 8, 10, 12 nA (with raster). Each run should be the greater of 1 hour or 1 M events with trigger bit 0 (i.e., if trigger bit 0 / all triggers = f, then take 1 M / f events).
- Fine-adjust raster to optimize raster radius vs. luminosity (only during day shift).
- Take production data at beam current where average R1 DC occupancy is 5-6%
- Sunday 13:00 change target (possibly later but no earlier)
- 2nd target: Empty. Increase beam current as occupancy / trigger rate / currents allow - will require beam blocker in place (ask Rafo for calibration constants).
- Turn all detectors back on. Take a beam alignment run WITHOUT LHe and WITHOUT raster.
- Re-establish raster from before and take a 2 hour run with standard running condition (still no LHe).
- Repeat filled with LHe (75% level).
- As time permits, take a zero field alignment run (special trigger: rgc_300MeV_v1.6_zero.trg). No LHe. Try 1-2 nA beam (watch occupancies).
- 3rd target: raster calibration target
- Use raster calibration target to calibrate Vpp, offset, and Voltage->position in rastermon and CCDB. (Requires experts like Eugene, Maurik or Sebastian)
- Reduce current and over-raster the target (turn all CD HV off or in safe mode). Observe rastermon - increase Vpp in 0.2 V steps in both x and y until you see MOST of the target rim. (Offset back to zero!)
- Use the information from rastermon to determine the relative position of the target. Work with target group (J. Brock) to adjust target until it is centered on the raster pattern.
- 5th target: ND3
- Cold irradiation at 50 nA
- Anneal
- Start of production data taking.
NOTE: the relative ordering of these runs can be adjusted to minimize overhead for the target group and take maximum advantage of beam time.
Cold Irradiation Process
In this process we want to add the irradiation of the target by increasing the beam current. For this CLAS must be off .
Procedure:
- Turn off ALL high voltages, but put MVT in "safe" mode.
- Normal raster size (and FSD interlock)
- Insert the FCup beam blocker.
- You have to allow MCC increase the Fast Shutdown levels to Midstream: 20000, Downstream: 2000000 (i.e. 10x what they are now.) Then ask for 50 nA beam, increasing "slowly" from 20 nA while you watch for FSD or high counts on the beam line monitors.
- Irradiate the target for about 2 hours actual beam time, with this high beam current and raster size. Actual 2hours will probably take 3 hours on the clock.
- Repeat if time allows
- Target must be annealed and polarized to assess effect of this procedure.
5-pass (10.55 GeV) Running conditions
- Torus at 100% current, inbending electrons. Setpoint = +3770 A (Readback = +3766 A)
- Solenoid setpoint +2417.5 A
- Establish optimal compromise between raster size (if possible, 9 mm radius), luminosity (goal: 10 nA = 10^35), and background.
- Run duration 100M events or 4 hours, whichever comes first.
- For empty target runs, increase beam current as much as possible.
DAQ configuration
- Configuration PROD66/PROD66_PIN, trigger file rgc_300MeV_v2.2_Q2_1.5GeV2.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:
- Quit ALL running instances of mon12 and rastermon
- "cancel", "reset"
- "configure", "download", "prestart", "go"
- restart mon12 and rastermon
- 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 9/4/22
Solenoid set-point of 2417.5 A results in read back 2419.57 A and exactly 5.00 T field on center Raster settings
- x: Vpp=3.4 V offset =-0.3V
- y: Vpp=3.25 V offset =+0.2V (changed from +0.4V on July 14, changed from -0.1 on July 1 at 21:00, changed Vpp from 2.2 and offset from 0.25 on 8/12)
- Fundamental Period = 2 s
- The correct raster calibration constants should be automatically loaded by rastermon - see https://logbooks.jlab.org/entry/4004055 - if not, enter them through "Config" by hand.
Nominal Beam Positions
- 2H01, X = -2.4 mm, Y = +2.4mm
- 2C24A, X = -2.0 mm, Y = +0.6 mm
- 2C21A, X = -0.36 mm, Y = +0.5 mm
- Orbit lock ONLY if raster is OFF
FSD Thresholds (to be updated)
- Upstream: 2000 Hz
- Midstream: 2000 Hz
- Downstream: 100000 Hz (1e5)
- BOM: 1000000 Hz
- 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.
Known issues
- ECAL: ECAL_HV_SEC2_WI_E36 is off as it does not hold voltage
- tdcecal6 and tdcecal1 rocs: These rocs could show errors in the DAQ screen. If so, check roc-rates, trigger rates and monitoring plots. If all looks okay, continue data taking.
- DC: hole in sector 3, superlayer 6, would likely need a major physical repair on the chamber itself
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):
- Zoom for 24-7 communication with counting house: https://jlab-org.zoomgov.com/j/1619881100
- Passcode REQUIRED: 927417
- Remind the expert in the counting house to restart their zoom, if necessary
- Remote VNC connection instructions: https://logbooks.jlab.org/entry/3906039
- All necessary applications should be avaible from the desktop menu (left/right click on the desktop)
- EPICS GUIs should be accessed ONLY via the desktop menu or by running clascss-remote.
- Remote Demonstration Video (150 MB)
Shift Worker Tasks
Once per run:
- Screenshots: submit to logbook only if you capture the information with beam ON
- Beamline Overview, in VNC or Web Browser
- CLAS12 Trigger rates and DAQ status
- RGC Polarized Target GUI - under Beamline on CSS
- Upload monitoring plots to logbook
- Standard spectra (mon12): look at the spectra: Reference, current, and 5 most recent runs. You can choose a different reference run, the reference numbers refer to logbook entries.
- Raster Monitoring: upload RasterMon plots to the logbook (use "Log Entry" button on RasterMon screen at bottom-right corner)
- Make a log entry with the photograph of the polarized target run valve (hallbcam04)
Once per shift:
- Fill the shift checklist
- Log screen shots of RICH temperature and scaler maps. Log in RICH logbook.
Regularly:
- reset & check spectra frequently (every 30 - 60 minutes)
- Some plots in the online mon12 have a choice of histogram sets per sector, select buttons at the bottom of the plot. That means you have to look at all sectors for these histograms.
- The logbook entry shows all histograms.
- Log the strip charts in time intervals according to the x-axis time span, using the liveplot configuration Beamline4Logbook_visibleH
- how to get the strip charts: CS-Studio Tools: Strip Charts, livePlot
- right-click on the livePlot screen and select "Load a Configuration"
- the configuration "Beamline4Logbook_" provides the beam current, position information and halo counter rates
- right-click on the screen and select "Make Elog Entry", make sure to log to HBLOG and not ELOG
- in Web Browser: Upstream/Midstream Halo Counters, Downstream Halo Counters, Beam Currents, BPM Positions
- how to get the strip charts: CS-Studio Tools: Strip Charts, livePlot
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