Difference between revisions of "Run Group C"

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  * 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!
 
  * 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!
  
−
== '''Short Term Schedule Wednesday Owl-Swing''' ==
+
== '''Short Term Schedule Th, Oct 20, 2022''' ==
 
* Run duration: 100M events or 4 hours, whichever comes first.
 
* Run duration: 100M events or 4 hours, whichever comes first.
 
* Current: 8 nA
 
* Current: 8 nA
 
* Note, BOM is not installed for this experiment
 
* Note, BOM is not installed for this experiment
−
* If HWP is changed by Hall A (they will notify us) stop run and start new run after HWP change is finished.
+
* If HWP is changed by Hall A (they will notify us) stop run and start new run after HWP change is finished
  
 
to do:
 
to do:
 
* Continue production on ND3
 
* Continue production on ND3
−
* The beam seems to scrape the bottom of the cell, we need to move it up a bit/shrink it
+
* The beam seems to scrape the bottom of the cell, we need to move it up a bit/shrink it (raster adjustments) - started at 9:30
−
* Maybe raster adjustments are necessary
 
−
** Accumulate rastermon histograms during one run and log
 
 
* Decide on new reference mon12
 
* Decide on new reference mon12
 
* Monitor the beam charge asymmetry on MyaViewer: work at the injector should have reduced it considerably
 
* Monitor the beam charge asymmetry on MyaViewer: work at the injector should have reduced it considerably
Line 134: Line 132:
 
* Solenoid setpoint inverted (Oct 14 2022) -2417.5 A  
 
* Solenoid setpoint inverted (Oct 14 2022) -2417.5 A  
 
* Solenoid setpoint +2417.5 A (normal conditions RGA-M)
 
* Solenoid setpoint +2417.5 A (normal conditions RGA-M)
−
<!--
+
 
−
=== SHORT RANGE PLAN (last update September 27, 2022) ===
 
−
* Bring beam back to the hall on the tagger dump, follow standard proceedings. Do harp scans (10nA). Afterward do Moller run with 1/2 wave plate OUT.
 
−
* Then establish beam to FC. Raster must be ON. Check if beam goes cleanly through. You might need to adjust raster, check with RC and/or beamline expert.
 
−
* Production data on NH3 with NEGATIVE polarization with 6nA beam. First run with PROD66_PIN config. afterwards PROD66 config.
 
−
* We will continue with NH3 until the Maintenance Day (Thursday 9/29). Change HWP from OUT to IN during Swing shift today (Wednesday 9/28).
 
−
* During Maintenance day, we will do a TE on NH3 and then switch to CH2 target.
 
−
* We need to check for bleedthrough when HallC increases current. Ask MCC to do this (switching off HallB laser and check beam current in HallB with just C and D on).
 
−
* <font color=blue>In general, we should take data with the PROD66 configuration. Once or twice a day (BEFORE and AFTER a HWP flip or target polarization change), take a run with the PROD66_PIN (same trigger file in both cases). PROD66_PIN should have at least 20 M events.</font>
 
−
* 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". ND3 may have to be annealed between target polarization changes.
 
−
* Do a RICH Recovery procedure 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.  If RICH recovery procedure fails to fix the problem the first time, try again one more time. If the second RICH recovery attempt does not fix the problem  call RICH expert and keep taking data.
 
−
-->
 
−
<!--
 
−
=== <font color=green>Start-up after Configuration Change 3-sept</font>  ===
 
−
# First target: 2 cm diameter C target (+ LHe) - '''DONE'''
 
−
## 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
 
−
# Continue C with LHe - '''DONE'''
 
−
## 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: raster calibration target - '''DONE''' 9/4 15:30
 
−
## Take photos of raster calibration target before insertion, so we know what to look for.
 
−
## Insert beam blocker for FC. Check that FC blocker calibration from last time we did this (before the changeover) are loaded. This is just a precaution in case we need to increase the beam current.
 
−
## Take a run (roughly 1 hour) with NO LHe, same raster settings as of now, and increase the beam current to get enough trigger rate (5kHz) as long as the DC occupancies don't exceed 6%
 
−
## Use high-statistics rastermon and mon12 data with raster calibration target to calibrate Vpp, offset, and Voltage->position in rastermon and CCDB. (Requires experts like Eugene, Maurik or Sebastian)
 
−
## 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.
 
−
# 3rd target: Empty. PARTIALLY DONE. Remaining to do (later, when there's an opportunity to change back to the Empty target):
 
−
## First '''reduce''' current to about 2 nA and over-raster the target (turn all CD HV off or in safe mode). Observe rastermon - increase Vpp in 0.2 V steps in x and then y until you see MOST of the target rim OR we get FSD trips from halo counters. '''DONE'''
 
−
## Ask Eugene to ramp down Solenoid and Torus
 
−
## Empty LHe and turn off raster (Vpp = 0, offsets nonzero).  Take a zero field alignment run (special trigger: rgc_300MeV_v1.6_zero.trg). No LHe. Try 1-2 nA beam (watch occupancies). Take 4-hour runs.  Get 20M events total. '''DONE'''
 
−
## Ask Eugene to turn ON Solenoid and Torus.  Ask MCC to remask solenoid.  Turn off beam during magnet ramp.
 
−
## Alignment run
 
−
### Call Yuri to restore MVT HV to normal operation. 
 
−
### Increase beam current as occupancy / trigger rate / currents allow.  If you can increase beam past 15 nA, then put in the beam blocker and call Rafo for calibration constants.
 
−
### Take a two hour beam position calibration run (change trigger to standard DAQ configuration [see below]) WITHOUT LHe and WITHOUT raster (ask MCC to mask raster FSD).
 
−
### Call Chris Keith, Radcon or MCC, and the RC when the run starts to notify them of a target change in 2 hours..
 
−
## Take a 2 hour run with standard running condition including raster but no LHe. (Beam blocker in, beam current 15-20 nA)
 
−
## Take 4-hour run WITH LHe at normal level.
 
−
# Install carbon target
 
−
## take carbon data with normal raster and full 4He (raster unmasked). 6 nA, standard configuration (PROD66 - NOT PIN) and trigger.
 
−
# 4th target: ND3
 
−
## Noon Tuesday: ask MCC to turn off beam. We will need RadCon. Target group will come and remove C target and install ND3 2cm dia. target.
 
−
## After target is filled with LHe, target group will do a measurement of polarization with microwave.  Then we ask for beam back.
 
−
## Cold irradiation (begin around beginning of Swing shift). See also below.
 
−
### Put beam blocker in, and turn off all HV to all detectors (BMTs in safe mode).
 
−
### Use our standard raster pattern (see below - check position on all BPMs). Raster FSD must be Unmasked.
 
−
### Start with 15 nA beam. If nothing trips, keep increasing up to 50 nA. (You will have to increase the downstream halo counter threshold - see below and/or check with Eugene).
 
−
### NOTE: NO data will be taken in this configuration. However, you can start a "junk run" to check the raster pattern with rastermon - only the random/pulser panel should be filled.
 
−
### Beam should go away sometime around 7 Wednesday morning (maintenance day). Wait until about 9 and then go to controlled access. We will need Radcon and target group.
 
−
## Remove ND3 target, anneal, and reinsert. Take baseline, TE, and begin polarizing.
 
−
## Start of production data taking on ND3 once beam returns. First move beam slightly more to the left by setting raster x-offset to -0.55 V. Also reduce y-raster Vpp to 3.15 V. Check occupancy vs. raster position (mon12) and rastermon as well as DAQ rates, electron lifetime, beam halo monitor rates and average R1 DC occupancies to see if this improve things.-->
 
−
<!-- ==== <font color=green> Cold Irradiation Process</font> ====
 
−
In this process we want to add the irradiation of the target by increasing the beam current. For this <font color="red"> <b>CLAS must be off </b></font>.<br />
 
−
<b>Procedure: </b>
 
−
* 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 15 nA while you watch for FSD or high counts on the beam line monitors.
 
−
* Irradiate the target for about 16 hours , with this high beam current and raster size.
 
−
* Target must be annealed and polarized to assess effect of this procedure.
 
−
## (NOTE: the beam raster MUST be on at all times, hence you cannot do a harp scan at 2H01). You can temporarily put in the beam viewer to take a look at the profile, but then it has to be taken out. Some of the above is also described in the manuals - Physics-Quality Beam and Performing Møller Runs under “Shift Documentation” tab of the Run Group C run wiki.
 
−
# <b> We want to re-do the optimization for the raster settings. </b> Start a run and using both the new mon12 plots created by Raffa, and the FT asymmetry (mon12). Change the raster offset by -0.1 in X and Y and check that the amount of "red areas" are similar for all 6 sectors and no yellow or white, and the FT asymmetry is roughly 0. In the previous reference runs, the beam was too much to the right and too high. (Note that the target is large enough in diameter so that you shouldn’t hit the edge - confirm with your rastermon. Note that whenever you change the raster offset, you will have to observe how 2H01 x and y change, and tell MCC that those are the new values to shoot for. (You can tell them to stop trying to center the beam on 2H01 while you are trying out different offsets - otherwise you might end up working at cross-purpose).
 
−
# Note the final raster parameters and positions on 2H01 - update the whiteboard and th "Short-Term Schedule” accordingly, and inform MCC. <br /> You don’t need to start a new run for every new set of raster parameters - you can just clear mon12 and rastermon. Ideally someone should write down what you observe and log the raster DC occupancies and the FT asymmetry plots for each setting.
 
−
# Once the raster is satisfactory, start a long production run. We want at least 50M events.
 
−
# Depending on the report from the FT (Forward Tagger) analysis, we may go back to doing the 50nA "cold irradiation" process. Check the RC.
 
−
-->
 
−
<!-- * END EMPTY TARGET RUNNING. Ask target group to install new target (CH2 - check with RC/Sebastian/Target Group).
 
−
** CH2 run (fill with LHe)
 
−
*** Raster on, FSD unmasked, no orbit lock.
 
−
*** Take FC blocker out, go back to 4 nA and standard position on 2H01
 
−
*** Take production data with standard trigger rgc_300MeV_v1.2_no_DC.trg, PROD 66.
 
−
-->
 
−
<!-- * 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.
 
−
-->
 
  
 
== <font color=blue> DAQ configuration </font> ==  
 
== <font color=blue> DAQ configuration </font> ==  
Line 267: Line 173:
 
* Midstream: 2000 Hz
 
* Midstream: 2000 Hz
 
* Downstream: 100000 Hz (1e5)
 
* Downstream: 100000 Hz (1e5)
−
* BOM: 1000000 Hz
+
* BOM: 1000000 Hz (not used for RG-C)
 
* 5 ms dwell time
 
* 5 ms dwell time
  
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* With 6 nA beam, the upstream counters should read zero.  
 
* With 6 nA beam, the upstream counters should read zero.  
 
* The Midstream ones should read 0-20 Hz or so.
 
* The Midstream ones should read 0-20 Hz or so.
−
* Greatly increased rates may indicate bad beam tune or bleed-through from other Halls.  
+
* Greatly increased rates may indicate bad beam tune or bleed-through from other Halls.
−
<!--
 
−
* 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.
 
−
-->
 
  
 
= Shift Expert =
 
= Shift Expert =

Revision as of 08:41, 20 October 2022

[edit]

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

Role Phone Number
Hall B Run Coordinator (757) 575-7540 (cell)
Hall B Physics Division Liaison (757) 876-1789 (cell)
MCC 7048
Crew Chief 7045
Crew Chief (757) 876-3367 (cell)
Program Deputy (757) 876-7997 (cell)
RadCon (757) 876-1743 (cell)
Gate House Guard 5822
Location Phone Number
Hall B Floor 5165
Hall B Space Frame 5170 and 5171
Hall B Forward Carriage 5371
Hall B Gas Shed 7115
Hall B Counting House 5244 (Shift Expert)
Hall B Counting House (757) 329-4846 (Shift Expert cell)
Hall B Counting House 5245 or 5126 (Shift Worker)
Hall A Counting House 5501
Hall C Counting House 6000
Hall D Counting House 5504
Hall B System Phone Number On-Call Person
Engineering (757) 748-5048 (cell)
(757) 897-9060 (cell)		 Engineering On-Call (primary)
Denny Insley (secondary)
Slow Controls (757) 748-6922 (cell) Nathan Baltzell
Beamline (757) 303-3996 (cell) Eugene Pasyuk
DC (757) 218-4372 (cell)
(757) 748-5048 (cell)		 Florian Hauenstein (primary)
Engineering On-Call (secondary)
SVT/MVT/MM (757) 541-7539 (cell)
(757) 753-7769 (cell)		 Yuri Gotra (primary)
Rafo Paremuzyan (secondary)
ECAL (757) 810-1489 (cell) Cole Smith
FTOF/CTOF/CND (757) 344-7204 (cell) Daniel Carman
ALERT (757) 329-4844 (cell) Raphael Dupré
HTCC/LTCC (757) 344-7174 (cell) Youri Sharabian
FT (757) 344-1848 (cell) Raffaella De Vita
BAND (757) 310-7198 (cell) Florian Hauenstein
RICH (757) 344-3235 (cell)
(757) 748-6922 (cell)		 Christopher Dilks (primary)
Nathan Baltzell (secondary)
DAQ (757) 232-6221 (cell) Sergey Boiarinov
HYDRA (317) 550-9226 (cell) Torri Jeske
Authorized Hall B Solenoid/Torus Operators
Hall B Denny Insley, Morgan Cook, Eugene Pasyuk
Magnet Group Probir Ghosha, Renuka Rajput-Ghoshal
Detector Support Group Brian Eng, Pablo Campero, Tyler Lemon
DC Power Onish Kumar, Sarin Philip
  • 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: Susan Schadmand

  • (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

Medium-Term Run plan (FTout portion)

IMPORTANT SHIFT 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!

Short Term Schedule Th, Oct 20, 2022

  • Run duration: 100M events or 4 hours, whichever comes first.
  • Current: 8 nA
  • Note, BOM is not installed for this experiment
  • If HWP is changed by Hall A (they will notify us) stop run and start new run after HWP change is finished

to do:

  • Continue production on ND3
  • The beam seems to scrape the bottom of the cell, we need to move it up a bit/shrink it (raster adjustments) - started at 9:30
  • Decide on new reference mon12
  • Monitor the beam charge asymmetry on MyaViewer: work at the injector should have reduced it considerably
  • Moller run (with 1/2 plate OUT) maybe Friday

Run Plan: September - December 2022

GENERAL INFORMATION

  • Before leaving the hall and going to beam permit check that dome lights, forward carriage lights, and pie tower lights are OFF
  • Moller runs should be taken with 8-10 nA.
  • 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.
  • We have a new FSD condition for when 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.
  • Whenever you change the raster offset, ask MCC to NOT correct whatever happens on 2H01. Note new 2H01 values and inform MCC of the new 2H01 x and y values - then they can keep the beam at those positions.
  • 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.
  • 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.
  • Whenever the target type or polarization direction changes, or the half-wave plate status changes, make sure to enter a comment in the BEGIN RUN / END RUN comment box.
  • Whenever there is magnet trip due to cryo, also inform the target expert about the cryogenic issues
  • Do not change running conditions while a run is ongoing. This includes changing target polarization or HWP, etc.
  • The Faraday Cup power limit for the continuous operation was lifted up to 1 kW. For the remainder of the RGC the beam blocker should not be used https://logbooks.jlab.org/entry/4047791

5-pass (10.55 GeV) Running conditions

  • Torus at 100% current, inbending electrons. Setpoint = +3770 A (Readback = +3766 A)
  • Solenoid setpoint inverted (Oct 14 2022) -2417.5 A
  • Solenoid setpoint +2417.5 A (normal conditions RGA-M)


DAQ configuration

  • Configuration PROD66/PROD66_PIN, trigger file rgc_300MeV_v2.3_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 and you will run with the same configuration and trigger file, then: "prestart", "go"
    • If you are changing configuration (between PROD66 and PROD66_PIN) or trigger file: "cancel", "reset", "configure", "download", "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 19 Sept. 22 (updated October 14, 2022)

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 = 3.6 V, offset = -0.65 V
  • y: Vpp = 3.2 V, offset = -0.15 V
  • Fundamental Period = 2 s
  • The correct raster calibration constants should be automatically loaded by rastermon - if not, enter them through "Config" by hand:
  • f(x) = 0.0104*x + -25.5
  • f(y) = -0.0115*y + 24.4

Nominal Beam Positions

  • 2C21A, X = -0.4 mm, Y = +0.6 mm
  • 2C24A, X = -2.0 mm, Y = +0.6 mm
  • 2H01, X = -1.9 mm, Y = +1.0 mm
  • Orbit lock on 2C24 and 2H01 ONLY if raster is OFF, otherwise orbit lock on 2C21 and 2C24 (note: this appears as "stopped" on the beam line GUI).

FSD Thresholds

  • Upstream: 2000 Hz
  • Midstream: 2000 Hz
  • Downstream: 100000 Hz (1e5)
  • BOM: 1000000 Hz (not used for RG-C)
  • 5 ms dwell time

Reference plots and histograms

  • Harp Scans for Beam on Faraday Cup, 2H01 [1], more recent scan (3 Sept 2022): [2]
  • Harp Scans for Beam on 2C21 [3], more recent scan (3 Sept 2022): [4]
  • Harp Scan on Tagger Dump (3 Sept. 2022) [5]
  • Monitoring Histograms (18 Sept 2022) [6]
  • RasterMon (18 Sept 2022) [7]

Counter rates

  • With 6 nA beam, the upstream counters should read zero.
  • The Midstream ones should read 0-20 Hz or so.
  • Greatly increased rates may indicate bad beam tune or bleed-through from other Halls.

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.

  • Follow the Short Term Schedule as outlined by RC
    • includes Run Plan, DAQ configuration, and References and Standards
  • Keep shift summary up to date in HBLOG. Record all that happens.
  • Ensure that all monitoring plots are logged correctly and checked against the reference plots for every single run.
  • Polarized target:
    • Helicity-Latched Trigger GUI and the Helicity Trigger Asymmetry strip-chart (not accessible remotely) (example https://logbooks.jlab.org/entry/4041939).
    • In case of any issues, contact the polarized target expert on call.
    • Ice on the run valve
    • NMR running
      • The JLab Polarization Display is seen via a VNC window in the counting room. Here, the NMR Controls' blue bar must be moving, indicating that the NMR is running and the polarization is measured.
      • The NMR frequency needs to be controlled by hand. If you see target polarization (on the red graph) starting to drop, call the expert. They will guide you through the adjustment procedure. This will be in the electronics room by the door to the counting room, in the third crate from the right ("CR-6"). White box which says "EIO Tube" and has a red button at the top right, which says "Move", next to a display for "Position". This will be the one to press, under guidance of the target expert.
    • Alarms from System RG-C Polarized Target (alarm handler).
  • Do a RICH recovery (press the RICH Recovery button on the GUI) once daily during day shift, between runs. Please log in shift summary.
    • Note the automated "RICH Recovery" sequence already confirms RICH4 is up and accepting ssh connections before claiming success.
    • You have to "Cancel->Reset->Configure->Download->Prestart" before starting the next run.
  • Fill out BTA hourly. Click "Load from EPICS" to automatically fill the left side then correct as needed.
    • Accelerator beam time:
      • ABU: acceptable beam used (eg harp scans, calibrations, trigger settings, running)
        • 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.
      • BANU: beam acceptable but not used (eg radiator change or our problems)
      • BNA: beam not acceptable (eg tuning, drifting, not focused)
    • Experiment beam time
      • ER: experiment ready
      • PCC: planned configuration change (when beam is masked while radiators are moved, DAQ (roc rebooting, restarting runs)), if more than 5 minutes, put a short comment, eg harp scans or DAQ.
      • UED: unplanned experiment down (hardware failure)
    • Enter fields at tab "Shift Information"
    • Promptly send "Info for MCC" at 7:00, 15:00, and 23:00
    • Sign, viz log completed 8 hour sheet


In case of other questions or uncertainties of what to do, call the RC or PDL

(remote) shift worker: see dedicated Worker Shift tab above.

For REMOTE Shifts (offsite):

ATTENTION: If you plan to take (a) remote shift(s), you MUST test your setup (including VNC connection) at least 24 hours before your first shift!

Shift Worker Tasks

New: Use the new HBRUN logbook for automated and run-specific entries and screenshots, see https://logbooks.jlab.org/entry/4048698

Make the following log entries 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 CS-Studio
    • Helicity Trigger Asymmetry strip-chart (CS-Studio -> Helicity-Latched Trigger GUI Screen -> Menu -> livePlot). See more info below

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.
  • Check the life cam of the polarized target run valve for plumes or ice buildup (hallbcam04)
    • Make sure you refresh the web page! Its no longer necessary to put a snapshot into the logbook UNLESS something looks suspicious. In THAT case, immediately inform the target expert(s).
  • Log the strip charts in time intervals according to the x-axis time span, via right-click on the screen and selecting "Make Elog Entry". Make sure NOT to submit to ELOG.
    • Beam current and position strip-charts (CS-Studio -> Beamline -> Strip Charts)
    • Helicity Trigger Asymmetry strip-chart (CS-Studio -> Helicity-Latched Trigger GUI Screen -> Menu -> livePlot)
      • Example https://logbooks.jlab.org/entry/4041939) (not accessible remotely).
      • Select the 2nd variable from bottom (dark green) on all 3 strip charts to get a reasonable scale. Set the vertical scale on the bottom strip chart manually to have the same range for both variables, roughly from 0.5 to 0.9.


Clas12design.png

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