D2n Run Plan 2020-1pass
From HallCWiki
See d2n 1-pass Running page for additional detail.
Contents
- 1 NOTES
- 2 DONE Beam Energy Measurement (1 hour)
- 3 DONE Reference Cell Empty, Hydrogen (H2), Carbon Cross Sections (3--4 hours)
- 4 DONE No Target Run
- 5 DONE 3He Reference Cell Runs (N2 and 3He Pressure Curves, False Asymmetries) (5hrs ideal, 3 hrs min)
- 6 DONE Reference Cell He3 Cross Sections (1 hour)
- 7 DONE Polarized 3He Runs, 3He elastic and QE longitudinal Asymmetries (16 hours)
- 8 Polarized 3He Elastic Longitudinal Asymmetry (until end of 1-pass running)
NOTES
- If the ps1 setting is > 5 (true prescale > 17), then the EDTM rate must be increased
- See Hall C EDTM Pulser, use the dial to increase/decrease the rate -- Call the RC for instructions.
- ps1=0..5 then set EDTM rate to 120 (Default)
- ps1=6 then set EDTM rate to 240
- ps1=7 then set EDTM rate to 480
- Hall C Shift Crew must monitor the 'Parity DAQ' and run the
./FlipPCvaluesHallC
script on every IHWP change!!- Give Hall B a heads-up before the flips
- See Charge Feedback Parity DAQ in the How-tos
- Every time the Reference Cell contents are changed Shift Crew must make a log entry AND replace the post-it note on the Reference Cell control panel!
- Record the pressure in your Shift Summary Log at both Start and End of each run
- Fast Raster Coil 'B' is off when at 1-pass so the "FRB" raster plots will be empty/spikes. That is OK.
- The "FRA" Raster plots should look normal, however!
DONE Beam Energy Measurement (1 hour)
- Accelerator driven process -- will happen following initial beam checkout into the Hall
DONE Reference Cell Empty, Hydrogen (H2), Carbon Cross Sections (3--4 hours)
Goals - To measure carbon, hydrogen elastic cross sections as a cross check of data quality - To measure backgrounds from glass cell and beamline windows (Reference-VAC)
Setup - Beam Current: 5--15 uA and DAQ rate-limited, raster always ON (4mm diameter) - Target: Reference Cell: C-Foil, vacuum, and H2 @ 135 psig - Detectors: All scintillator bars on
Spectrometer Setup (with HMS 11.7 deg, SHMS 8.5 deg) - HMS setting: 11.7 deg, -2.08234 GeV/c (electron QE) -- Jan 3He elastic settings - SHMS setting: 8.5 deg, -2.12860 GeV/c (electron QE setting, but focus on 3He elastic events) -- Jan 3He elastic settings
Procedure - Set spectrometers at the required settings, ensure all scintillator bar HV is ON
- Move to Carbon-Foil - Keep beam current the same as the above Empty Cell run, check rates and prescale factors (Save PS file if changed). Goal is to reach (3.5-4)kHz DAQ rate on both HMS and SHMS. If rates too low, increase the beam current but do not exceed 30uA. If rates too high, prescale it down and do NOT drop current below 10uA unless raw rates in the pretriggers exceed 500 kHz. - Take one 45-minute run (both arms) - While this run is going, you can evacuate the reference cell if necessary
- Evacuate Reference Cell (to vacuum), record the pressure reading in the Start_Run entries. - Ask MCC for 10uA raster ON (4mm dia), check rates and prescale factors (Save PS file if changed). Goal is to reach (3.5-4)kHz DAQ rate on both HMS and SHMS. If rates too low, increase the beam current but do not exceed 30uA. If rates too high, prescale it down and do NOT drop current below 10uA unless raw rates in the pretriggers exceed 500 kHz. - Take one 45-minute run (both arms), make sure there are no less than 10,000 events for each of HMS and SHMS. - Record the pressure in your Shift Summary Log at both Start and End of each run
- Fill Reference Cell to 135 psig of hydrogen gas; - Keep beam current the same as the above Empty Cell run, check rates and prescale factors (Save PS file if changed). Goal is to reach (3.5-4)kHz DAQ rate on both HMS and SHMS. If rates too low, increase the beam current but do not exceed 30uA. If rates too high, prescale it down and do NOT drop current below 10uA unless raw rates in the pretriggers exceed 500 kHz. - Take one 45-minute run (both arms), apply ztar and W cut and make sure H2 elastic events from the H2 gas are no less than 10,000 for each of HMS and SHMS. - Record the pressure in your Shift Summary Log at both Start and End of each run
DONE No Target Run
Goals - To measure beam-line window contributions alone
Setup - Beam Current: 5--15 uA and DAQ rate-limited, raster always ON (4mm diameter) - Target: NO TARGET - Detectors: All scintillator bars on
Spectrometer Setup (with HMS 11.7 deg, SHMS 8.5 deg) - Same as above
Procedure - Take 30 minute run (both arms)
DONE 3He Reference Cell Runs (N2 and 3He Pressure Curves, False Asymmetries) (5hrs ideal, 3 hrs min)
** We did skip N2; only He3 was completed for this portion ** ** NOTE: Call RC at this point. We may skip the N2 setting and just do the 3He if the target polarization is OK **
Goals - For empty cell, to determine window background for elastic setting - For N2, need 5 points at 0.5, 1.0, 2, 4 and 8 atm, 10,000 N2 elastic events for each pressure setting and each spectrometer. - For 3He, need 6 points at 1, 2, 4, 6, 8 and 10 atm, 10,000 3He elastic events for each pressure setting and each spectrometer. - Reference cell must be filled with 3He last, and do NOT pump the 3He gas out! - Time: couple of hours assuming 50% beam efficiency
Setup - Beam Current: 5--10uA, raster always ON (4mm diameter). Do not drop currents below 10uA unless raw rates in the pretriggers exceed 500 kHz. - Target: Reference Cell, Empty, filled with N2, filled with 3He (last) - Detectors: We will need to keep only 2 scintillator bars ON to take mostly 3He elastic and limit quasi-elastic scattering events. - Use these settings: Scintillator Settings A1n notes: hclog 3756736, hclog 3760238 - HMS Detectors: turn off paddles 1-6 on 1X plane and paddles 1-6 on 2X plane - SHMS Detectors: keep only paddles 7,8 of 1X plane, and paddles 7,8,9 of 2X ON, all others off; - SHMS (continued): Also suggest for 1Y keep only 7 on, all others off, although this will depends on how well the collimators works
Spectrometer Setup (with HMS 11.7 deg, SHMS 8.5 deg) - HMS setting: 11.7 deg, -2.08234 GeV/c (electron QE) -- Jan 3He elastic settings - SHMS setting: 8.5 deg, -2.12860 GeV/c (electron QE setting, but focus on 3He elastic events) -- Jan 3He elastic settings
Procedure - Set spectrometers at the required settings, target at the Reference Cell position. - Make sure the correct scintillator bars are ON. - Start at for 5 uA raster ON (4mm dia), check trigger rates and PS factors. Ideally we would like to see (3.5-4)kHz DAQ rates. If rates are too high, use Prescaling (save PS file if changed). If rates are too low, increase beam current but do not exceed 30uA. Ensure that the livetimes are >80% in each arm.
Nitrogen Pressure Curve - Evacuate cell to vacuum and take one 20-minute run. - Fill the cell (slowly) to 380 Torr with N2, take one 20-minute run. - Fill the cell (slowly) to 1 psig, take one 20-minute run. - Fill the cell to 15 psig, take one 20-minute run. - Fill the cell to 45 psig, take one 20-minute run. - Fill the cell to 75 psig, take one 20-minute run. - Fill the cell to 105 psig, take two 30-min runs and flip the IHWP in between
He3 Pressure Curve - DoneEvacuate cell to vacuum and take one 20-minute run.- DoneFill the cell (slowly) to 380 Torr with He3, take one 20-minute run.- DoneFill the cell (slowly) to 1 psig, take one 20-minute run.- DoneFill the cell to 15 psig, take one 20-minute run.- DoneFill the cell to 45 psig, take one 20-minute run.- DoneFill the cell to 75 psig, take one 20-minute run.- DoneFill the cell to 105 psig, take one 20-minute run.- DoneFill the cell to 135 psig, take 1 30-min run- DoneFlip the IHWP and run the flipper script for the Parity DAQ Charge Feedback Parity DAQ- DoneFill the cell to 135 psig, take 1 30-min run
- Important: After these runs are completed, do NOT pump out the 3He gas!
Things to watch for - These reference cell runs must be taken with exactly the same spectrometer and scintillator settings as polarized 3He elastic asymmetry runs (see next). - Beam current should not be below 10uA (BCM accuracy) and should not be above 30uA (glass cell safety). - For each gas pressure setting (except for empty cells), need 10,000 events from gas alone (apply ztar cuts) for each of HMS and SHMS.
DONE Reference Cell He3 Cross Sections (1 hour)
- Reference Cell should already be set to 135 psig of He3 gas; - Turn ON all scintillator paddles - Check rates and prescale factors (Save PS file if changed). Goal is to reach (3.5-4)kHz DAQ rate on both HMS and SHMS. If rates too low, increase the beam current but do not exceed 30uA. If rates too high, prescale it down and do NOT drop current below 10uA unless raw rates in the pretriggers exceed 500 kHz. - Take one 45-minute run (both arms) - Record the pressure in your Shift Summary Log at both Start and End of each run
DONE Polarized 3He Runs, 3He elastic and QE longitudinal Asymmetries (16 hours)
Goals - To measure physics longitudinal asymmetry of 3He elastic (on SHMS) and QE (on HMS) scattering. - If precision is high, this cross checks PbPt from Moller and Target Polarimetry. - If precision is low, at the minimum we should determine the sign of asymmetries. - Experts must watch EDTM rate (Brad).
Setup - Beam Current: 10--15uA, raster always ON (4mm diameter) - Target: Polarized 3He Cell - Target spin direction: 180 deg (to start) - See Target Field Runplan for coil currents settings. - Time: total 12--16 hours of data taking, flip beam IHWP every ~4 hours. Do target NMR every 4--5 hours (ask TO), but always before and after the full data taking.
Spectrometer Setup (with HMS 11.7 deg, SHMS 8.5 deg) - HMS setting: 11.7 deg, -2.08234 GeV/c (electron QE) -- January setting - SHMS setting: 8.5 deg, -2.12860 GeV/c (electron QE setting, but focus on 3He elastic events) -- January setting
- Use these settings when requested below: Scintillator Settings - All bars are ON to start with - HMS Detectors: turn off paddles 1-6 (or 1-9) on 1X plane and paddles 1-6 (or 1-9) on 2X plane - SHMS Detectors: keep only paddles 7,8 of 1X plane, and paddles 7,8,9 of 2X ON, all others off; -SHMS (continued): Also suggest for 1Y keep only 7 on, all others off, although this will depends on how well the collimators worksA1n notes: hclog 3756736, hclog 3760238
Procedure - Set target at the Polarized 3He Cell position, spin 180 deg. (should be the current setting)
- DoneTake an NMR/pNMR before starting this section
- Ask MCC for 10 uA raster ON (4mm dia), check trigger rates. Goal is to reach (3.5-4)kHz DAQ rates. - If rates too high, adjust PS factors (save PS file if changed!) and/or drop beam current but do not go below 10uA unless raw rates in the pretriggers exceed 500 kHz. - If rates too low (unlikely), increase beam current but do not exceed 30uA.
* DoneTake 1 60-minute run (ALL BARS ON)
- DoneTurn off HMS scintillator bars as described above- DoneTurn off SHMS scintillator bar as described above* DoneTake 3 60-minute runs- Immediately check that you turned off the paddles you intended in the online monitor! See HCLOG 3851420
- DoneTake an NMR/pNMR
- DoneCall MCC and ask beam IHWP to be flipped. Need to inform other halls prior to the switch.- DoneFollow the instructions to run the 'Flipper script' in the Parity DAQ charge feedback system! See Charge Feedback Parity DAQ in the How-tos* DoneTake 4 60-minute runs
- DoneTake an NMR/pNMR
- DoneRotate target to Longitudinal/0; Update coil settings as needed
* DoneTake 4 60-minute runs
- DoneTake an NMR/pNMR- DoneCall MCC and ask beam IHWP to be flipped. Need to inform other halls prior to the switch.- Follow the instructions to run the 'Flipper script' in the Parity DAQ charge feedback system! See Charge Feedback Parity DAQ in the How-tos
* DoneTake 3 60-minute runs
* Updated Scintillator bar settings to cut hard on the E:QE ratio SHMS HV paddles ON: 1x: 7,8 2x: 7,8,9 1y: 7 2y: 10,11,12 HMS HV paddles ON: 1x: 10-16 2x: 10-16 1y: 4,5,6 2y: 4,5,6 [1]
* DoneTake 4 60-minute runs
- DoneTake an NMR/pNMR- DoneCall MCC and ask beam IHWP to be flipped. Need to inform other halls prior to the switch.- Follow the instructions to run the 'Flipper script' in the Parity DAQ charge feedback system! See Charge Feedback Parity DAQ in the How-tos
* DoneTake 4 60-minute runs
- DoneTurn all bars ON* DoneTake 1 60-minute run (ALL BARS ON)
- DoneTake an NMR/pNMR
Things to watch online - Ensure the correct scintillator bars are on (We need 3He elastic events in SHMS and QE events in HMS) - Apply z cuts to isolate events scattered from 3He gas (We do not want events from the glass windows!) - Apply W or dp cuts to isolate 3He elastic (SHMS) or QE(HMS) events from others. - For HMS, run online script to ensure we see physics asymmetry. Plot asymmetry as function of nu (=E-E'). - For SHMS, run online script to ensure we see physics asymmetry. Plot asymmetry as function of W(3He).
Predictions - QE asymmetry (HMS) predictions are given in hclog 3759756. - Elastic 3He asymmetry (SHMS) is predicted to be 2.5% on SHMS, with Pb=0.8, Pt=0.5 and fN2=0.9 gives Ameas=0.9%. - Important: would like to have more than 6% of the full rate on SHMS to come from 3He elastic.
Polarized 3He Elastic Longitudinal Asymmetry (until end of 1-pass running)
Goals - To measure the elastic 3He asymmetry in two SHMS settings: 13 deg (for ~8 hours) and 15.5 deg (~8--16 hours), and one HMS setting: 17 deg.
General Setup - Beam Current: 10-30 uA, raster always ON (4mm diameter) - Target: Polarized 3He Cell - Target spin direction: Longitudinal/0 deg - Trigger: 3/4 (ps1) - See Target Field Runplan for coil currents settings. - Time: Until end of run, Monday September 27th 07:00. - Momentum Setup(this should be the same as the previous runs, and stay unchanged till the end) - HMS setting: -2.08234 GeV/c - SHMS setting: -2.12860 GeV/c - Flip beam IHWP every ~4 hours - Do target NMR every 4-5 hours
Procedure - Set target at the Polarized 3He Cell position, longitudinal/0 (should be the same as before) - Set SHMS to 13.0 deg, -2.08234 GeV/c - Set HMS to 17.0 deg, -2.12860 GeV/c (The HMS will stay in this configuration until beam is off) - Trigger setup: Start with HMS PS1=0, SHMS PS1=5. All other PS = -1
- Turn on all scintillator paddles. (Shujie or Scott should show up at this point. If not, call Shujie. Phone number on white board)
- Ask MCC for 10 uA raster ON (4mm dia), check raw trigger rates on Prescaler GUI and post. Adjust beam current (keep between 5-30 uA) to reach (3.5-4)kHz DAQ rates at HMS PS1=1 (PS2, PS3, ...=0). - Adjust SHMS PS factors (save PS file if changed!) to reach 3.5 to 4KHz
- Take a 30 minutes run. - Meanwhile check that hodo paddle settings make sense for optimizing elastic events using the online monitor under (S)HMS ET Monitor->1-Pass->Hodoscope X-Paddles and Hodoscope Y-Paddles. Update the elastic cuts on online scripts, and decide the paddle settings call RC for questions - If ps1=0 (i.e. not prescaling) more paddles could be turned on in that arm to gather more data. Sequentially turn on paddles 6 .. 1 in that order until rates reach 3.5--4kHz. (Covering the QE electrons.)
-This is an example of hodo paddle settings. Goal is to keep all elastic events, and as many as possible QE events without using higher PS factors Scintillator Settings - HMS Detectors: turn off paddles 1-6 (or 1-9) on 1X plane and paddles 1-6 (or 1-9) on 2X plane - SHMS Detectors: keep only paddles 7,8 of 1X plane, and paddles 7,8,9 of 2X ON, all others off;
- DONE Turn off certain hodo paddles as desired. bring up beam current if HMS rates are below 3.5k-4k with PS1=0, then adjust SHMS prescale factor to reach 3.5k-4kHz. Post screenshots on logbook.
- Take 2 1-hour runs in each arm (SHMS 13 deg; HMS 17 deg) - Label each 1/2, 2/2 in Run Comments to keep track
- around 4:30pm, ake NMR/pNMR measurement and Call MCC and ask beam IHWP to be flipped. Hall B is noticed already. - Follow the instructions to run the 'Flipper script' in the Parity DAQ charge feedback system! See Charge Feedback Parity DAQ in the How-tos
- Take 2 1-hour runs in each arm (SHMS 13 deg; HMS 17 deg), if possible - Label each 1/2, 2/2 in Run comments to keep track
TBD: Starting 8pm on Sunday at the latest (could get here earlier if there is good beam) - Rotate the SHMS to 15.5 deg (leave momentum setting at p=-2.08234 GeV/c). - HMS is unchanged (17.0 deg and p=-2.12860 GeV/c).
- (Shujie or Scott should show up at this point. If not, call Shujie. Phone number on white board)
- Turn on all SHMS hodo paddles, keep HMS unchanged
- Request 10 uA beam and adjust current and prescales to reach a trigger (ps1) rate of 3.5-4 kHz. This will likely mean increasing the beam current. - take a 30 minutes run. Meanwhile check that SHMS hodo paddle settings make sense for optimizing elastic events using the online monitor under (S)HMS ET Monitor->1-Pass->Hodoscope X-Paddles and Hodoscope Y-Paddles. Update the elastic cuts on online scripts, and decide the paddle settings call RC for questions
- Use as low a prescale as possible and as high a current (up to 30 uA) as possible to maximize the rate on the HMS at 17 deg as well. - Verify that hodo paddle settings make sense for optimizing elastic events using the online monitor under (S)HMS ET Monitor->1-Pass->Hodoscope X-Paddles and Hodoscope Y-Paddles as soon as you start a run. If ps1=0 (i.e. not prescaling the data), more paddles can be turned on to gather more data beginning with paddles covering the QE electrons (6 .. 1). Call the RC if you are unsure.
- Turn off certain SHMS hodo paddles as desired.Bbring up beam current if HMS rates are below 3.5k-4k with PS1=0, then adjust SHMS prescale factor to reach 3.5k-4kHz. Post screenshots on logbook.
** You will then repeat the pattern below until beam is off at Monday, 7am - Take 4 1-hour runs in each arm (SHMS 15.5 deg; HMS 17 deg) - Label each 1/4, 2/4, .. 4/4 in Run Comments to keep track - Take NMR/pNMR measurement (should be about 4--5 hours since the last one) - Call MCC and ask beam IHWP to be flipped. Need to inform other halls prior to the switch. - Follow the instructions to run the 'Flipper script' in the Parity DAQ charge feedback system! See Charge Feedback Parity DAQ in the How-tos ** And repeat (4 runs, NMR, flip IHWP; etc) until beam is off **
AFTER BEAM IS OFF at Monday 7am - Take final NMR/pNMR measurement, and relax :-)
Things to watch online - Ensure the correct scintillator bars are on (We need 3He elastic events!) - Check PS1 and PS2 trigger raw rates. Call RC if they are very different. - Run online script to ensure we see physics asymmetry. HMS and SHMS should see the same asymmetry. Asymmetry should flip sign with beam IHWP switch and target spin flip.
Important Scripts
- Elastic Electron Count Script:
- Location: /home/cdaq/polhe3/production/hallc_online/analysis/elastic/el_asym_(s)hms.cxx
- Description: These scripts count the number of elastic electrons in a data run after applying various cuts.
- Usage: To use these scripts with the correct relative paths they must be executed from the ~/polhe3/production/hallc_online directory. They can be executed as 'root -b -q "analysis/elastic/el_asym_shms.cxx(11091)"'.
- Output: The analysis plots can be found in ~/polhe3/production/hallc_replay/MON_OUTPUT/ANALYSIS_HISTOS/run#_analyzed/.
- Elastic Asymmetry Script:
- Location: /home/cdaq/polhe3/production/hallc_online/analysis/elastic/asym_elastic.py
- Description: This script will calculate the elastic asymmetry for runs listed in /home/cdaq/polhe3/production/hallc_online/database/(S)HMS_run_table.csv. The momentum and angle arguments will display only runs with settings near those given. The elastic counts used for this calculation come from calling the el_asym_(s)hms.cxx scripts mentioned above. Acceptance cuts for elastic electrons can be changed in those scripts.
- Output: The plot of the asymmetries is written to ~/polhe3/production/hallc_online/progress/asym_elastic_(s)hms.png.
- Usage: 'python3 asym_elastic.py SHMS -p 2.17 -a 8.5 -t 0.1 --estimate=0.026 --factor-qe=0.80 --date-start=2020-01-12'
- Positional Arguments:
- arm Spectrometer Arm (HMS or SHMS)
- Positional Arguments:
- Optional Arguments:
- -h, --help show this help message and exit
- Optional Arguments:
- -p MOMENTUM momentum setting (GeV)
- -a ANGLE angle setting (degree)
- -t TOLERANCE absolute tolerance for settings
- --date-start START start date
- --date-end END end date
- --counts-min CMIN minimum event counts for valid elastic runs
- --estimate ESTIMATE estimated asymmetry for this setting (without any corrections)
- --factor-qe F_QE dilution factor from Quasi-Elastic asymmetries
- --run-script run count script if output does not exist
- Paddle Optimization Script:
- Location: /home/cdaq/polhe3/production/hallc_online/analysis/hodo/draw_paddles_(s)hms.cxx
- Usage: From /home/cdaq/polhe3/production/hallc_online/ execute 'root -b -q "analysis/hodo/draw_paddles_shms.cxx(9788)"'.
- Output: The analysis plots can be found in ~/polhe3/production/hallc_online/paddle_plots/.