Difference between revisions of "Tune Photon Beam and collect data for initial detector checkout"
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* '''Goal''': Tune the photon beam to go through the collimator, the experimental target area, and into the photon beam dump. | * '''Goal''': Tune the photon beam to go through the collimator, the experimental target area, and into the photon beam dump. | ||
* Expected Schedule: | * Expected Schedule: | ||
| − | ** | + | ** See start dates in the run coordination meeting pages [https://halldweb1.jlab.org/wiki/index.php/Run_Coordination_Meetings#Meeting_General_Agenda here]. The initial photon beam and detector checkout is then expected to last 4 days. |
* Responsibility: HallD, Accelerator, RadCon. | * Responsibility: HallD, Accelerator, RadCon. | ||
* Priority: Most activities are High, but includes Moderate and Low priority activities. | * Priority: Most activities are High, but includes Moderate and Low priority activities. | ||
* '''Prerequisites''': | * '''Prerequisites''': | ||
| − | # Tagger hall equipment remain removed. < | + | # Tagger hall equipment remain removed. <span style="font-size:21px">☑</span> |
# Hall D controlled quadrupole MQPAD00 remained turned off. <math>\Box</math> | # Hall D controlled quadrupole MQPAD00 remained turned off. <math>\Box</math> | ||
#* Responsibility: MCC | #* Responsibility: MCC | ||
| Line 13: | Line 13: | ||
# Monitoring available in counting room: | # Monitoring available in counting room: | ||
#* DAQ screens <math>\Box</math> | #* DAQ screens <math>\Box</math> | ||
| + | #** [https://hdops.jlab.org/wiki/index.php/Data_Acquisition_Shift Procedure for bringing up DAQ] (System expert: Sergey Furletov) | ||
#* online monitoring screens <math>\Box</math> | #* online monitoring screens <math>\Box</math> | ||
| − | #* slow control screens <math>\Box</math> | + | #** [https://hdops.jlab.org/wiki/index.php/Online_Monitoring_Shift Procedure for bringing up online-monitoring] (System expert: David Lawrence) |
| − | #* alarm | + | #* slow control screens and alarm handlers <math>\Box</math> |
| + | #** [https://hdops.jlab.org/wiki/index.php/Slow_Controls_Shift Procedure for bringing up slow control and alarm screens] (System experts: Hovanes Egiyan (EPICS), Yi Qianq (EPICS/PXI).) | ||
#* [https://logbooks.jlab.org/book/halld Hall D electronic logbook] open <math>\Box</math> | #* [https://logbooks.jlab.org/book/halld Hall D electronic logbook] open <math>\Box</math> | ||
| − | # | + | # Scaler acquisition operational for rate azimuthal asymmetry monitoring and initial detector study. <math>\Box</math> (Sergey Furletov, Mark Dalton) |
| − | # | + | # 1.5 µm Al (1.7·10<sup>-5</sup> R.L.) radiator in. |
| − | #* | + | #* System expert: Hovanes Egyian |
| − | #* [ | + | #* [[Tagging_Spectrometer_Shift#Move_Amorphous_Radiator | Procedure for inserting radiator]] |
| − | # | + | # Collimator: |
| − | # | + | #*remains in blocking position (similar to the electron beam tune phase). <math>\Box</math>. |
| − | #* System expert: Hovanes Egiyan. | + | #*The motion must be calibrated. <span style="font-size:21px">☑</span> |
| − | #* | + | #** System expert: Hovanes Egiyan. |
| − | # | + | #** [[Tagging_Spectrometer_Shift#Move_Amorphous_Radiator | Procedure for moving amorphous radiator]] |
| − | # | + | # Upstream profiler installed in the Collimator Cave, surveyed in order to find the position of the nominal beam center <span style="font-size:21px">☑</span> |
| − | # Active Collimator operational. < | + | # Downstream profiler installed in front of photon beam dump, surveyed. <span style="font-size:21px">☑</span> |
| − | #* System expert: Richards Jones | + | # Active Collimator operational. <span style="font-size:21px">☑</span> |
| − | + | #* System expert: Alex Barnes, Richards Jones | |
# Pair spectrometer field on, converter retracted. <math>\Box</math> | # Pair spectrometer field on, converter retracted. <math>\Box</math> | ||
#* System expert: Alexander Somov | #* System expert: Alexander Somov | ||
| − | #* | + | #* [https://hdops.jlab.org/wiki/index.php/Pair_Spectrometer_Shift Procedure for turning on Pair Spectrometer field and inserting/removing converters ] |
| − | + | # Solenoid on at quench-safe current ~300A. | |
| − | # Solenoid | + | |
#* System expert: Yi Qiang <math>\Box</math> | #* System expert: Yi Qiang <math>\Box</math> | ||
#* Procedure for setting the Solenoid current: Call Yi Qiang (primary, office: 269-7237, cell: 358-2146) or George Biallas (alternate, office: 269-7535, cell: 813-1179) | #* Procedure for setting the Solenoid current: Call Yi Qiang (primary, office: 269-7237, cell: 358-2146) or George Biallas (alternate, office: 269-7535, cell: 813-1179) | ||
#* [https://hdops.jlab.org/wiki/index.php/Solenoid_Shift#EPICS_Interface_-_Main_Menu Procedure for monitoring the Solenoid current] | #* [https://hdops.jlab.org/wiki/index.php/Solenoid_Shift#EPICS_Interface_-_Main_Menu Procedure for monitoring the Solenoid current] | ||
# No target in place (air and material along the beamline makes a few R.L.). <span style="font-size:21px">☑</span> | # No target in place (air and material along the beamline makes a few R.L.). <span style="font-size:21px">☑</span> | ||
| − | + | # Sweeping electromagnet in the collimator cave on. <math>\Box</math> | |
| + | # The noise in the beam profilers was measured in the absence of electron beam. <math>\Box</math> | ||
| + | #* System expert: Hovanes Egyian | ||
| + | #* [[Beam_Line_Detectors_Shift#Beam_Profilers | Procedure for reading signals of upstream profiler]] | ||
| + | *The ATLis corresponding to the runplan below can be found [http://opsweb.acc.jlab.org/CSUEApps/atlis/task/14461 here] | ||
'''Activities''' | '''Activities''' | ||
* '''First period: Initial photon beam and detector checkout) ''' | * '''First period: Initial photon beam and detector checkout) ''' | ||
| − | # (High) Produce acceptable photon beam | + | # (High) Produce acceptable photon beam. (Time estimate 4h including 100% contingency) |
| − | # | + | ## Re-establish the CW electron beam on 1.5 µm Al (1.7·10<sup>-5</sup> R.L.) radiator, with 50 nA electron beam centered in the Tagger Dump and photon beam centered on the upstream profiler (Accelerator/Hall D) (time estimate: 1h) <math>\Box</math> |
| − | # | + | ### Verify that e<sup>-</sup> beam is acceptable, that is: |
| − | # | + | #### Beam width is fine (10<sup>-2</sup> wings). Ask this information to MCC for the location of HARP IHA5C11A. |
| − | # | + | #### Electron beam position on the Tagger Dump BPM is good and photon beam centered on the upstream profiler. |
| − | #** | + | ####*[https://hdops.jlab.org/wiki/index.php/Check_beam_position_at_the_tagger_dump Procedure to monitor the e<sup>-</sup> beam position at Tagger dump] |
| − | #* | + | ###* Good rate expected in the profiler (for the 1.7*10<sup>-5</sup>radiator and the 50 nA): 750 kHz. (Rate in one central fiber: 34kHz). Noise rate from backsplash is estimated to be similar. |
| − | #* | + | ###* System expert: Hovanes Egyian |
| − | + | ###* [https://hdops.jlab.org/wiki/index.php/beam_table_fall14 Table of beam characteristics (for reference)] | |
| − | + | ### Ion chamber calibration (Time estimate 2h including 100% contingency) | |
| − | # | + | ###* Responsibility, accelerator, see [http://opsweb.acc.jlab.org/CSUEApps/atlis/task/14461 Accelerator ATLis] |
| − | #* | + | ## Retract the 1.7·10<sup>-5</sup> R.L. radiator <math>\Box</math> (time estimate: 10 min) <math>\Box</math>. Measure the signal in the beam profiler in the absence of amorphous radiator (time estimate: 30min). Compare with previous measurement to assess possible e- beam halo scrapping. <math>\Box</math>. Re-insert the 1.7·10<sup>-5</sup> R.L. radiator <math>\Box</math> (time estimate: 10 min) <math>\Box</math> |
| − | # | + | ##* System expert: Hovanes Egyian |
| − | # | + | ##* [[Tagging_Spectrometer_Shift#Move_Amorphous_Radiator | Procedure for inserting radiator]] |
| − | #* | + | ## Check the radiation levels in the Tagger Hall and the Collimator Cave <math>\Box</math> (time estimate: 10 min) <math>\Box</math> |
| − | + | ##* System expert: Alexandre Deur (CARMS)/Hovanes Egyian (halo counters) | |
| − | # (High) Tune photon beam | + | ##* [https://hdops.jlab.org/wiki/index.php/How_to_read_temporary_CARMS Procedure to monitor CARMs and Halo counters] |
| − | # | + | # (High) Tune photon beam at the primary collimator location. (Time estimate 10h including 100% contingency) |
| − | # | + | ## Using the upstream Profiler find the beam center position with respect to the nominal position (time estimate: 4h) <math>\Box</math> |
| − | #* | + | ##* System expert: Hovanes Egyian |
| − | # | + | ##* [[Beam_Line_Detectors_Shift#Beam_Profilers | Procedure for reading signals of upstream profiler]] |
| − | # | + | ## Adjust photon beam position while keeping e<sup>-</sup> beam centered on tagger dump (Time estimate: 30min). Obtain a first determination of the accelerator scale. |
| − | # | + | ##* Ask MCC to move the beam to the nominal position, using the last e<sup>-</sup> beam line corrector. <math>\Box</math> |
| − | # | + | ##* Calibrate the accelerator scale for x and y. That is, find the relation between the corrector currents and beam position at the profiler location. Obtain this information from MCC and log it in the Electronic logbook. In the same time, fill a table correlating 1) the beam position from the upstream profiler; 2) Either the position indicated by MCC or equivalently the current in the correctors and 3) the AD00 BPM reading at the photon dump. Do it for x and y. This procedure provides a rough accelerator scale. The fine one will be provided by the Active Collimator. <math>\Box</math> |
| − | #* | + | ### Monitor that the electron beam position at the Tagger dump remains acceptable, i.e. within +/-5mm. <math>\Box</math> |
| − | # | + | ###* [https://hdops.jlab.org/wiki/index.php/Check_beam_position_at_the_tagger_dump Procedure to monitor the e<sup>-</sup> beam position at Tagger dump] |
| − | #* Check the | + | ### Keep monitoring radiation levels in the Tagger Hall and the Collimator Cave <math>\Box</math> |
| − | # | + | ## Insert 5mm collimator in beam position. |
| − | #* | + | ##* System expert: Hovanes Egyian |
| − | # | + | ##* [[Beam_Line_Detectors_Shift#Move_Collimator | Procedure for moving the primary collimator]] |
| − | + | ## Check the photon beam position at the photon Dump using the downstream Beam Profiler <math>\Box</math> | |
| − | # | + | ##* System expert: Hovanes Egyian |
| − | #* | + | ##* [https://hdops.jlab.org/wiki/index.php/Beam_position_from_profilers Procedure for reading signals of downstream profiler] |
| − | #* | + | ## <span style="color:red">Call RadCon before to do this step. For safety reasons, this can only be done during day time.</span> Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Use 5mm step size. Leave the collimator in the nominal position (0.5 mm hole at the nominal center) . Meanwhile, monitor the Pair Spectrometer Rate (time estimate: 10min/step -> 2h) <math>\Box</math> |
| − | # | + | ##* System expert: Richard Jones/Hovanes Egyian |
| − | # | + | ##* [[Beam_Line_Detectors_Shift#Move_Collimator | Procedure for moving the primary collimator]] |
| − | # | + | ##* [[https://hdops.jlab.org/wiki/index.php/Check_PS_Scaler_rates | Procedure for monitoring Pair Spectrometer scalers]] |
| − | # | + | ##* [[https://halldweb1.jlab.org/wiki/index.php/Active_Collimator Procedure for reading beam X-position from the Active collimator]] |
| − | # (High) measure the beam position with the Pair Spectrometer's harp | + | ## (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in X accordingly (time estimate: 10min) <math>\Box</math> |
| − | # | + | ## (High) Ask MCC to move the beam in X ±10 mm around nominal beam position at collimator. Use 2mm step size. Verify that the beam X-position from the Active Collimator matches (time estimate: 10min/step -> 1h40) <math>\Box</math> |
| − | # | + | ## (High) Ask MCC to move the beam in Y ±10 mm around nominal beam position at collimator. Use 2mm step size. calibrate the Active Collimator response (time estimate: 10min/step -> 1h40) <math>\Box</math> |
| − | #* | + | ## (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in Y accordingly (time estimate: 10min)<math>\Box</math> |
| − | # | + | # (High) measure the beam position with the Pair Spectrometer's harp (time estimate: 2h, including 100% contigency) |
| − | # | + | ## Verify that the pair spectrometer magnet is on at nominal field (1.8T, 991A). (time estimate: parasitic). <math>\Box</math> |
| − | + | ##* System expert: Alexandre Somov | |
| − | + | ##* [https://hdops.jlab.org/wiki/index.php/Pair_Spectrometer_Shift Procedure for monitoring pair spectrometer B-field] | |
| − | + | ## Turn on the low-granularity PS counters <math>\Box</math>, DAQ <math>\Box</math> and controls <math>\Box</math> (time estimate: parasitic). | |
| − | #* | + | ## Install a PS foil converter (time estimate: 5 min) |
| − | # | + | ##* [https://hdops.jlab.org/wiki/index.php/Pair_Spectrometer_Shift Procedure to insert foil converter] |
| − | #* | + | ## Measure the rate (time estimate: 30min) <math>\Box</math> |
| − | # | + | ##* Expected rate: 110 Hz (coincidence. No significant noise expected); 430 Hz for one arm (without accounting for noise) for a 50 nA beam and 1.5 µm Al (1.7·10<sup>-5</sup> R.L.) radiator. |
| − | # | + | ## Using the PS wire scanner, measure the position of the beam spot at the converter (time estimate: 20 min) <math>\Box</math> |
| − | # | + | ##* Procedure: Call Hovanes. (For this first time use, the expert is necessary to interpret the data) |
| − | # (High) GlueX detector checkout | + | ## (High) Insert the 10<sup>-3</sup> PS foil converter and start taking data - keep the PS running (time estimate: 5 min, then parasitic) <math>\Box</math> |
| − | # | + | # (High) Assess beam alignment from the 3 measured points (Upstream profiler/Active collimator, Pair Spec., Downstream profiler). If good, turn on the start counter and check rates. Document them in the logbook. Turn the ST off. |
| − | # | + | # (High) Orbit Lock commissioning (Time estimate 1h including 100% contingency) |
| − | # | + | #* Responsibility, accelerator, see [http://opsweb.acc.jlab.org/CSUEApps/atlis/task/14461 Accelerator ATLis] |
| − | # | + | # (High) Verify target/Start Counter alignment & Initial GlueX detector checkout |
| − | #* (High) | + | ## Go to controlled Access. Call Alex. Somov (office: 269-5553, cell: 224-8587) and let him know that the initial detector checkout will start soon. |
| − | # | + | ## Ramp down the solenoid to 0 Gauss in order to allow beam line radiological survey (the magnetic field may disturb the survey instruments). |
| − | # | + | ## As soon as the survey is done, set the solenoid current to 1000 A (time estimate: 2 hours, but done during steps 3 and 4) <math>\Box</math> |
| − | # | + | ##* System expert: Yi Qiang |
| − | #* | + | ##* Procedure for setting the Solenoid current: Call Yi Qiang (primary, office: 269-7237, cell: 358-2146) or George Biallas (alternate, office: 269-7535, cell: 813-1179) |
| − | # | + | ##* [https://hdops.jlab.org/wiki/index.php/Solenoid_Shift#EPICS_Interface_-_Main_Menu Procedure for monitoring the Solenoid current] |
| − | # | + | ## Meanwhile, insert the 1cm CH2 target (1.2% RL). |
| − | #* | + | ##* [https://hdops.jlab.org/wiki/index.php/Procedure_installing_solid_target procedure for installing the target] |
| − | #* | + | ##* System expert: Alexandre Deur/Matt Marchlik |
| − | # | + | ## (High) Close the Hall, restore the beam, turn on the detectors (this can be done in parallel: |
| − | # | + | ## Turn BCAL detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 1h, including 100% contingency) |
| − | # | + | ##* System expert: Elton Smith |
| − | #* | + | ##* [https://hdops.jlab.org/wiki/index.php/Barrel_Calorimeter_Shift#Routine_operation Procedure for turning on BCal] |
| − | # | + | ##* [[https://hdops.jlab.org/wiki/index.php/How_to_read_BCAL_Scalers Procedure to check rates]] |
| − | # | + | ## Turn Start Counter detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 4h, including 100% contingency) <math>\Box</math> |
| − | #* | + | ##* [[Start_Counter_Commissioning|Procedure for turning on Start Counter]] |
| − | #* | + | ##* System expert: Eric Pooser/Mark Ito |
| − | # | + | ##* [https://hdops.jlab.org/wiki/index.php/Howto_read_ST_scallers Procedure to check rates] |
| − | # | + | ## Turn FCAL detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 1h, including 100% contingency) <math>\Box</math> |
| − | # | + | ##* System expert: Manual Lara |
| − | # | + | ##* [https://hdops.jlab.org/wiki/index.php/Forward_Calorimeter_Shift#Routine_operation Procedure for turning on FCal] |
| − | # | + | ##* [https://hdops.jlab.org/wiki/index.php/Forward_Calorimeter_Shift#Rates_Monitoring Procedure to check rates] |
| − | # | + | ## Adjust target/ST alignment (time estimate: 2h, including 100% contingency) . |
| − | # | + | ###Check effect of +/-1cm collimator x-translation on Start Counter and FCAL rates. (0.5 cm steps, 15 min/steps -> 1h, including 100% contingency) |
| − | # | + | ### Minimize possible large asymmetries by adjusting the collimator or target assembly (Assume 1h). |
| − | # | + | ## Turn TOF detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 4h, including 100% contingency) <math>\Box</math> |
| − | # | + | ##* System expert: Mark Ito |
| − | # | + | ##* [https://hdops.jlab.org/wiki/index.php/Time-of-Flight_System_Shift#Turning_High_Voltage_On Procedure for turning on TOF] |
| + | ##* [https://hdops.jlab.org/wiki/index.php/Time-of-Flight_System_Shift#Monitoring_Scaler_Rates Procedure to check rates] | ||
| + | ## Turn CDC detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h, including 100% contingency) <math>\Box</math> | ||
| + | ##* System expert: Benedikt Zihlmann. | ||
| + | ### Some HV card on the inner-most layer are powered by Verne-Keibler HV supplies. Current limit is set to 0.1 muA and a video camera visible in the control room watches the currents. The voltages are set to nominal CDC levels (2100V). | ||
| + | ### If currents are stable and under 500nA, then the remaining HV cards on the CDC can be turned on. These are connected to the normal CAEN supplies. Verify that no channels trip during this process. | ||
| + | ##* [https://hdops.jlab.org/wiki/index.php/Central_Drift_Chamber_Shift Procedure for turning on CDC] | ||
| + | ## Turn FDC detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h, including 100% contingency) <math>\Box</math> | ||
| + | ##* System expert: Lubomir Pentchev | ||
| + | ##* Follow the [[Turn_FDC_ON|procedure for turning on FDC]] after beam alignment. | ||
| + | ## Trigger settings for a combination of BCAL and FCAL signals, adjust the timings and the thresholds. Estimate: 8h, including 100% contingency). | ||
| + | ##* System expert: Alexander Somov | ||
| + | ## Take data for all the subsystems (time estimate: 8 h) <math>\Box</math> | ||
| + | ##* [[https://hdops.jlab.org/wiki/index.php/Data_Acquisition_Shift Procedure to turn on DAQ]] | ||
'''End Initial photon beam and detector checkout''' | '''End Initial photon beam and detector checkout''' | ||
Latest revision as of 09:06, 31 October 2014
Tune Photon Beam
- Goal: Tune the photon beam to go through the collimator, the experimental target area, and into the photon beam dump.
- Expected Schedule:
- See start dates in the run coordination meeting pages here. The initial photon beam and detector checkout is then expected to last 4 days.
- Responsibility: HallD, Accelerator, RadCon.
- Priority: Most activities are High, but includes Moderate and Low priority activities.
- Prerequisites:
- Tagger hall equipment remain removed. ☑
- Hall D controlled quadrupole MQPAD00 remained turned off.
- Responsibility: MCC
- Hall D: Detectors turned off. Exceptions: Profiler, possible BCAL, outer rings of the FCAL
- Monitoring available in counting room:
- DAQ screens
- Procedure for bringing up DAQ (System expert: Sergey Furletov)
- online monitoring screens
- Procedure for bringing up online-monitoring (System expert: David Lawrence)
- slow control screens and alarm handlers
- Procedure for bringing up slow control and alarm screens (System experts: Hovanes Egiyan (EPICS), Yi Qianq (EPICS/PXI).)
- Hall D electronic logbook open
- DAQ screens
- Scaler acquisition operational for rate azimuthal asymmetry monitoring and initial detector study. (Sergey Furletov, Mark Dalton)
- 1.5 µm Al (1.7·10-5 R.L.) radiator in.
- System expert: Hovanes Egyian
- Procedure for inserting radiator
- Collimator:
- remains in blocking position (similar to the electron beam tune phase). .
- The motion must be calibrated. ☑
- System expert: Hovanes Egiyan.
- Procedure for moving amorphous radiator
- remains in blocking position (similar to the electron beam tune phase).
- Upstream profiler installed in the Collimator Cave, surveyed in order to find the position of the nominal beam center ☑
- Downstream profiler installed in front of photon beam dump, surveyed. ☑
- Active Collimator operational. ☑
- System expert: Alex Barnes, Richards Jones
- Pair spectrometer field on, converter retracted.
- System expert: Alexander Somov
- Procedure for turning on Pair Spectrometer field and inserting/removing converters
- Solenoid on at quench-safe current ~300A.
- System expert: Yi Qiang
- Procedure for setting the Solenoid current: Call Yi Qiang (primary, office: 269-7237, cell: 358-2146) or George Biallas (alternate, office: 269-7535, cell: 813-1179)
- Procedure for monitoring the Solenoid current
- System expert: Yi Qiang
- No target in place (air and material along the beamline makes a few R.L.). ☑
- Sweeping electromagnet in the collimator cave on.
- The noise in the beam profilers was measured in the absence of electron beam.
- System expert: Hovanes Egyian
- Procedure for reading signals of upstream profiler
- The ATLis corresponding to the runplan below can be found here
Activities
- First period: Initial photon beam and detector checkout)
- (High) Produce acceptable photon beam. (Time estimate 4h including 100% contingency)
- Re-establish the CW electron beam on 1.5 µm Al (1.7·10-5 R.L.) radiator, with 50 nA electron beam centered in the Tagger Dump and photon beam centered on the upstream profiler (Accelerator/Hall D) (time estimate: 1h)
- Verify that e- beam is acceptable, that is:
- Beam width is fine (10-2 wings). Ask this information to MCC for the location of HARP IHA5C11A.
- Electron beam position on the Tagger Dump BPM is good and photon beam centered on the upstream profiler.
- Good rate expected in the profiler (for the 1.7*10-5radiator and the 50 nA): 750 kHz. (Rate in one central fiber: 34kHz). Noise rate from backsplash is estimated to be similar.
- System expert: Hovanes Egyian
- Table of beam characteristics (for reference)
- Ion chamber calibration (Time estimate 2h including 100% contingency)
- Responsibility, accelerator, see Accelerator ATLis
- Verify that e- beam is acceptable, that is:
- Retract the 1.7·10-5 R.L. radiator (time estimate: 10 min) . Measure the signal in the beam profiler in the absence of amorphous radiator (time estimate: 30min). Compare with previous measurement to assess possible e- beam halo scrapping. . Re-insert the 1.7·10-5 R.L. radiator (time estimate: 10 min)
- System expert: Hovanes Egyian
- Procedure for inserting radiator
- Check the radiation levels in the Tagger Hall and the Collimator Cave (time estimate: 10 min)
- System expert: Alexandre Deur (CARMS)/Hovanes Egyian (halo counters)
- Procedure to monitor CARMs and Halo counters
- Re-establish the CW electron beam on 1.5 µm Al (1.7·10-5 R.L.) radiator, with 50 nA electron beam centered in the Tagger Dump and photon beam centered on the upstream profiler (Accelerator/Hall D) (time estimate: 1h)
- (High) Tune photon beam at the primary collimator location. (Time estimate 10h including 100% contingency)
- Using the upstream Profiler find the beam center position with respect to the nominal position (time estimate: 4h)
- System expert: Hovanes Egyian
- Procedure for reading signals of upstream profiler
- Adjust photon beam position while keeping e- beam centered on tagger dump (Time estimate: 30min). Obtain a first determination of the accelerator scale.
- Ask MCC to move the beam to the nominal position, using the last e- beam line corrector.
- Calibrate the accelerator scale for x and y. That is, find the relation between the corrector currents and beam position at the profiler location. Obtain this information from MCC and log it in the Electronic logbook. In the same time, fill a table correlating 1) the beam position from the upstream profiler; 2) Either the position indicated by MCC or equivalently the current in the correctors and 3) the AD00 BPM reading at the photon dump. Do it for x and y. This procedure provides a rough accelerator scale. The fine one will be provided by the Active Collimator.
- Monitor that the electron beam position at the Tagger dump remains acceptable, i.e. within +/-5mm.
- Keep monitoring radiation levels in the Tagger Hall and the Collimator Cave
- Ask MCC to move the beam to the nominal position, using the last e- beam line corrector.
- Insert 5mm collimator in beam position.
- System expert: Hovanes Egyian
- Procedure for moving the primary collimator
- Check the photon beam position at the photon Dump using the downstream Beam Profiler
- System expert: Hovanes Egyian
- Procedure for reading signals of downstream profiler
- Call RadCon before to do this step. For safety reasons, this can only be done during day time. Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Use 5mm step size. Leave the collimator in the nominal position (0.5 mm hole at the nominal center) . Meanwhile, monitor the Pair Spectrometer Rate (time estimate: 10min/step -> 2h)
- System expert: Richard Jones/Hovanes Egyian
- Procedure for moving the primary collimator
- [| Procedure for monitoring Pair Spectrometer scalers]
- [Procedure for reading beam X-position from the Active collimator]
- (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in X accordingly (time estimate: 10min)
- (High) Ask MCC to move the beam in X ±10 mm around nominal beam position at collimator. Use 2mm step size. Verify that the beam X-position from the Active Collimator matches (time estimate: 10min/step -> 1h40)
- (High) Ask MCC to move the beam in Y ±10 mm around nominal beam position at collimator. Use 2mm step size. calibrate the Active Collimator response (time estimate: 10min/step -> 1h40)
- (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in Y accordingly (time estimate: 10min)
- Using the upstream Profiler find the beam center position with respect to the nominal position (time estimate: 4h)
- (High) measure the beam position with the Pair Spectrometer's harp (time estimate: 2h, including 100% contigency)
- Verify that the pair spectrometer magnet is on at nominal field (1.8T, 991A). (time estimate: parasitic).
- System expert: Alexandre Somov
- Procedure for monitoring pair spectrometer B-field
- Turn on the low-granularity PS counters , DAQ and controls (time estimate: parasitic).
- Install a PS foil converter (time estimate: 5 min)
- Measure the rate (time estimate: 30min)
- Expected rate: 110 Hz (coincidence. No significant noise expected); 430 Hz for one arm (without accounting for noise) for a 50 nA beam and 1.5 µm Al (1.7·10-5 R.L.) radiator.
- Using the PS wire scanner, measure the position of the beam spot at the converter (time estimate: 20 min)
- Procedure: Call Hovanes. (For this first time use, the expert is necessary to interpret the data)
- (High) Insert the 10-3 PS foil converter and start taking data - keep the PS running (time estimate: 5 min, then parasitic)
- Verify that the pair spectrometer magnet is on at nominal field (1.8T, 991A). (time estimate: parasitic).
- (High) Assess beam alignment from the 3 measured points (Upstream profiler/Active collimator, Pair Spec., Downstream profiler). If good, turn on the start counter and check rates. Document them in the logbook. Turn the ST off.
- (High) Orbit Lock commissioning (Time estimate 1h including 100% contingency)
- Responsibility, accelerator, see Accelerator ATLis
- (High) Verify target/Start Counter alignment & Initial GlueX detector checkout
- Go to controlled Access. Call Alex. Somov (office: 269-5553, cell: 224-8587) and let him know that the initial detector checkout will start soon.
- Ramp down the solenoid to 0 Gauss in order to allow beam line radiological survey (the magnetic field may disturb the survey instruments).
- As soon as the survey is done, set the solenoid current to 1000 A (time estimate: 2 hours, but done during steps 3 and 4)
- System expert: Yi Qiang
- Procedure for setting the Solenoid current: Call Yi Qiang (primary, office: 269-7237, cell: 358-2146) or George Biallas (alternate, office: 269-7535, cell: 813-1179)
- Procedure for monitoring the Solenoid current
- Meanwhile, insert the 1cm CH2 target (1.2% RL).
- procedure for installing the target
- System expert: Alexandre Deur/Matt Marchlik
- (High) Close the Hall, restore the beam, turn on the detectors (this can be done in parallel:
- Turn BCAL detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 1h, including 100% contingency)
- System expert: Elton Smith
- Procedure for turning on BCal
- [Procedure to check rates]
- Turn Start Counter detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 4h, including 100% contingency)
- Procedure for turning on Start Counter
- System expert: Eric Pooser/Mark Ito
- Procedure to check rates
- Turn FCAL detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 1h, including 100% contingency)
- System expert: Manual Lara
- Procedure for turning on FCal
- Procedure to check rates
- Adjust target/ST alignment (time estimate: 2h, including 100% contingency) .
- Check effect of +/-1cm collimator x-translation on Start Counter and FCAL rates. (0.5 cm steps, 15 min/steps -> 1h, including 100% contingency)
- Minimize possible large asymmetries by adjusting the collimator or target assembly (Assume 1h).
- Turn TOF detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 4h, including 100% contingency)
- System expert: Mark Ito
- Procedure for turning on TOF
- Procedure to check rates
- Turn CDC detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h, including 100% contingency)
- System expert: Benedikt Zihlmann.
- Some HV card on the inner-most layer are powered by Verne-Keibler HV supplies. Current limit is set to 0.1 muA and a video camera visible in the control room watches the currents. The voltages are set to nominal CDC levels (2100V).
- If currents are stable and under 500nA, then the remaining HV cards on the CDC can be turned on. These are connected to the normal CAEN supplies. Verify that no channels trip during this process.
- Turn FDC detector on. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h, including 100% contingency)
- System expert: Lubomir Pentchev
- Follow the procedure for turning on FDC after beam alignment.
- Trigger settings for a combination of BCAL and FCAL signals, adjust the timings and the thresholds. Estimate: 8h, including 100% contingency).
- System expert: Alexander Somov
- Take data for all the subsystems (time estimate: 8 h)
End Initial photon beam and detector checkout
Next step: One week pause in running for Tagger electronic reinstallation and data analysis.
