PRad Weekly Meetings

PRad phone meetings are held every Friday at 11:00 am EST.

2014

August 1

• Participants: Chao, Eugene, Josh, Kondo, Kris, Mahbub, Mikhail, Weizhi, Xuefei, Zhihong
• Minutes:
  1. HyCal work: Need to measure the real size of the central hole next week. This information is also needed to finalize the design of GEM.
  2. Chiller: Leakages are fixed, will test the chiller next week
  3. High Voltage: CPU box of the bad crates are uninstalled and placed on a table on the 0th floor, An expert named Robert is supposed to survey them
  4. Vacuum Box: Hall C is using a similar window (72 inches round shape), will communicate with them to see if we can get the material from the same vendor. So it is possible to go through our original design of the vacuum box window.
  5. File:GEM Design.pdf by Kondo (7 pages)

July 25

• Participants: Chao, Dipangkar, Eugene, Josh, Kris, Li, Mahbub, Mehdi, Mikhail, Weizhi, Xuefei, Zhihong
• Minutes:
  1. HyCal work: see Li's slides below. Work needs to be done on interlocks and cables between counting house and hall. Need to think about extra conductors for the target
  2. Josh: Chris is able to talk to all the motors of the positioner through a LabView interface.
  3. Eugene:
     • Ordered two 2024 T3 Clad Al sheets: 0.025" and 0.032" thick (48 feet x120 feet).
     • Design of the target stand is almost done.
     • Mahbub: Beam Scheduling Request has been sent to Volker for review and will need approval from Chris Keith, Graham and Radcon.
  4. Mehdi: Will have meeting with Dave K., Bob M., Eugene and Gary on Monday to decide for the design of the thin window and vacuum box flange.
• Talks:
  1. File:HyCal work.pdf by Li (8 pages)

July 18

• Participants: Ashot, Chao, Dipangkar, Eugene, Haiyan, Kondo, Josh, Li, Mahbub, Mehdi, Weizhi, Xuefei, Zhihong
• Minutes:
  1. HyCal Work:
     • Transporter works fine. HyCal is up and all the cables on top have been successfully connected.
     • Thin Window: Mehdi/Dave, max size of Al sheet is 4 feet x 12 sheet. Too small for the ~5 feet diameter window. George Bialas knows Butch Dillon Townes who could make larger windows. Need to wait before redoing the design (square window) of the vacuum box.
  2. Mehdi: vacuum box is ~$80k. Will ask companies for large blanks.
  3. All: need to think about procedure to install and protect the thin window.
• Talks:
  1. File:DAQ update.pdf by Chao (5 pages)

July 10

• Participants: Ashot, Chao, Dipangkar, Eugene, Haiyan, Josh, Li, Mahbub, Mehdi, Weizhi, Xuefei, Zhihong
• Minutes:
  1. HyCal Work:
     • Need to check HV+signal cables. All UVA module channels have been checked one by one. Only one bad channel (26 on module W22), the modules has been replaced and works fine.
     • Doug will to a pressure test of the water cooling system.
     • First attempt to talk to the transporter failed
  2. Eugene/Bob: Design of the target stand will take 2-4 weeks before procurement. Expect to have it within 10 weeks.
  3. Haiyan: Workshop at Mainz about charge radius was very interesting. People are very interested in the outcome of PRad. Preliminary results from PSI shows Muonic and electron Helium4 Lamb shift measurements agree with each other. MUSE will need few more years to be ready.
• Talks:
  1. DAQ_update.pdf by Chao (7 pages)

June 27

• Participants: Ashot, Chao, Eugene, Haiyan, Josh, Li, Mahbub, Mehdi, Zhihong
• Minutes:
  1. Eugene:
     • HyCal is in the Hall, the mechanical parts of the transporter are installed, the electrical parts will be installed soon. Cabling and setting up environment for EPICS variables is work in progress.
     • HyCal chiller is in place and eventually will be controlled by EPICS.
     • Work on the beamline will require some sporadic help.
  2. Ashot: will send the scope of work to Doug after the meeting so that work in the hall can start on Monday
  3. Mehdi:
     • received a quote for the updated design of the vacuum box from Meyer. Need to wait for Pfeiffer to take a decision.
     • will talk to Hall B engineer/technician to setup the window test.
  4. Haiyan: DOE supplemental proposal has been funded for the GEM project.
• Talks:
  1. beamline.pdf by Eugene (2 pages)

June 20

• Participants: Ashot, Chao, Eugene, Li, Mahbub, Mehdi, Xuefei, Zhihong
• Minutes:
  1. Chao: DAQ work in HallB is on going (mainly cleaning)
  2. Mehdi: Will get the quote for vacuum box only. The stands can be design later and build by a local vendor. Boxes are more time sensitive so we need to place the order as soon as possible
  3. Mehdi: will talk to Dave for the window test (need estimation of the material, cost and manpower)
• Talks:
  1. Collimators.pdf by Chao (6 pages)

June 13

• Participants: Ashot, Chao, Kondo, Dipangkar, Eugene, Josh, Li, Nilanga, Mahbub, Mehdi
• Minutes:
  1. Kondo: will have a final design after his visist to CERN in September, need to count 3-6 month after that to build the detector. (See talk below)
  2. Eugene: HyCal will be move to the Hall on Thursday June 19th. First task will be to open it and proceed to a visual inspection of the optical connections and light monitoring system and test them. By mid July, HyCal will be installed on the transporter

• Talks:
  1. Source.pdf by Li (5 pages)
  2. GEM.pdf by Kondo (7 pages)

June 6

• Participants: Ashot, Chao, Kondo, Dipangkar, Eugene, Li, Nilanga, Mahbub, Mehdi
• Minutes:
  1. Ashot has a set of 30 ADC we can use.
  2. Mahbub is going to ask for an extension of the MRI.
  3. Dipangkar will have a postdoc 100% at JLab to work on PRad.
  4. Nilanga: Condo is in charge of the design of the GEM, will present an update next week.
  5. Eugene: Need to decide the beamline configuration. According to Arne at the Users Meeting, the beam and the machine is and will not be perfect for the commissioning (expect 20 beam trips/hour ). So it is important to have harp to measure the beam spot and halo. We have option on where to put them.
     • Keep the one upstream from the tagger magnet
     • HPS will put one in the alcove.
     • we can use the 3rd harp from the goniometer and put just upstream of the target system. This is for us the best option.
• Talks:
  1. thin_window.pdf by Gary (5 pages)
  2. simulation_DAQ.pdf by Chao (8 pages)

May 30

• Participants: Alexander, Ashot, Chao, Eugene, Francois-Xavier, Li, Mahbub, Mehdi, Zhihong
• Minutes:
  1. Bob Miller will work on the target chambers stand.
  2. Gary/Mehdi: Finalizing the design of the box (see talks), work on the stand and get a more accurate quote from vendors.
  3. Li will produce the r vs z background plot: include the vertex info to see if the background mainly come from the flange or the pipe.
  4. Chao will work on the collimator simulation.

• Talks:
  1. background.pdf by Li (1 page)
  2. Drawings.pdf by Gary (2 pages)

May 9

• Participants: Ashot, Chao, Dipangkar, Eugene, Francois-Xavier, Haiyan, Josh, Li, Mahbub, Zhihong

• Minutes:
  1. Based on Li's simulation, the flange will introduce about 2% background to the first angular bin (0.8 - 1.05 degree). This background rate is low, thus it may be rejected by tracking. It will be verified by further simulation study. (The dimensions of the flange in the code may be changed according to the real design.)
  2. Zhihong obtained the fiber samples, he is waiting for the tools for cutting and polishing.
  3. Target chamber: lack of blank flanges and bellows in the delivery. The order and shipment information needs to be checked.
  4. GEM: the order can be placed quickly. Nilanga will attend the collaboration meeting.
  5. Move of HyCal: The work will start in June. Students need to make sure the trainings are up-to-date.

• Talks:
  1. Flange Effect by Li (8 pages)

May 2

• Participants: Alexander, Ashot, Chao, Dipangkar, Eugene, Francois-Xavier, Haiyan, Josh, Li, Mahbub, Mehdi, Sergei, Zhihong

• Minutes:
  1. Chao will implement the 1mm iron HyCal window into his simulation
  2. Sergei:
     • Start moving HyCal May 28th (on transporter or cart? Cart would be a good idea so that we can start testing it but this could interfere with work in the hall), July 9th testing
     • electronics: The old fastbus have long cables and 34 pin connectors. For Flash ADC, we will need to replace the connector by LEMO connectors (total of ~$30k), the lead time is few month so we need to order them asap. The ADC are right now used by HPS. Need to ask Volker to use the CLAS ADC.
     • DAQ: be operational in August or September at the latest.
  3. Position detector: timing will probably be to tight for the SciFi traker and too expensive. Will continue with the prototype. GEM is our main option for tracking. Dipangkar will follow up with Nilanga.
• Talks:
  1. Q2 resolution by Ashot (9 pages)
  2. Thin Window and Vacuum Box by Gary (5 pages)
  3. Back Scattering in GEM or SFT by Chao (10 pages)
  4. Tracking by Chao (8 pages)
  5. SciFi Tracker Status by Zhihong (16 pages)
  6. Tracking by Li (4 pages)

April 25

• Participants: Alexander, Ashot, Chao, Dipangkar, Eugene, Francois-Xavier, Haiyan, Josh, Li, Mahbub, Mehdi, Zhihong

• Minutes:
  1. Eugene Pasyuk joined the PRad collaboration
  2. Mahbub: Chambers will be done and shipper next week. Estimated delivery at JLab: May 7th-8th. This may change due to customs potential delays.
  3. Haiyan will send to Volker and all relevant persons the drawings of the vacuum box for a design review.
  4. Based on Chao and Li simulations, a tube connected to the vacuum box and going through HyCal is the best option for background purposes.
  5. Next collaboration meeting Friday May 23rd.
• Talks:
  1. Updated design of the vacuum box by Gary (4 pages)
  2. Vacuum Box window simulation by Chao (7 pages)
  3. Vacuum box tube and flange simulation by Li (8 pages)
  4. New event generators for the PRad experiment by Alexander (10 pages)

April 18

• Participants: Alexander, Ashot, Chao, Dipangkar, Gary, Haiyan, Josh, Li, Mahbub, Mehdi, Zhihong

• Minutes:
  1. Josh/Gary: Will need a gate valve upstream of the target chamber. HallB should have one that we can use. Gary will check carefully if we can find a large enough sheet for the vacuum box window. He will focus on the box and the flange. He will proceed by iterations with Jlab to check the design.
  2. Josh:
     • We need to provide him with the stand for the chambers so that he does not need to build a temporary one for the test. Ashot: HallB will build the stands.
     • Give him the cell size we would like. Possibility of having different cell size but the surver will no longer be valid after a swap or cells.
     • Need to give him the clearance between the cell and heavy materials.
     • Need to give him the number and type of solid target. Ashot is working on that.
  3. Haiyan will follow up with Rolf and Volker about the procurement and design review of the vacuum box.
  4. Chao: will do a simulation, just for checking, of a 25mm diameter cell, 4mm diameter opening and 3mm thick copper tube.

• Talks:
  1. PrimEx Run Config by Mahbub (1 page)
  2. Drawing of the setup in HallB by Gary Swift (1 page)
  3. Drawing of the setup in HallB view 2 by Gary Swift (1 page)
  4. Drawing of the setup in HallB view 3 by Gary Swift (1 page)
  5. Simulation for target cell by Chao Peng (16 pages)

April 11

• Participants: Alexander, Ashot, Chao, Dipangkar, Francois-Xavier, Haiyan, Josh, Li, Mahbub, Mehdi, Zhihong

• Minutes:
  1. Ashot: Talked to Volker, good chance we could start moving HyCal to the hall 2-3 weeks earlier than planned. Will be difficult to get a russian calorimeter expert to come to Jlab due to DOE new rule. Maybe invite him through a University.
  2. Haiyan: talked to Rolf, HallC or D engineers will help to review and advise the vacuum box design. Timeline: get the design reviewed by June and start the procurement by July.
  3. Ashot, Mahbub: will work on the extension of the MRI funds.
  4. Zhihong, Chao will setup the DAQ and start the fiber test next week. Mahbub will ask Bogdan to borrow electronics and PMT.
  5. FX: Bob Miller agreed to work on the stand of the vacuum box given he has a preliminary design of the box
  6. Mehdi: vacuum box design: target cell center is at 550cm from HyCal surface. 20cm gap for tracking detector between the vacuum box window and HyCal -> 530cm between the target center and the vacuum box window.
  7. Li will pursue his effort on vaccum box window and pipe simulation with more statistic, will add collimator.
  8. Chao is working on updating the simulation will a new beam halo parameter.

• Talks:
  1. Flange and tube simulation data, bin by bin check by Li Ye (8 pages)

April 4

• Participants: Alexander, Chao, Chris, Dipangkar, Francois-Xavier, Josh, Li, Mahbub, Mehdi, Zhihong

• Minutes:
  1. Josh:
     • Need to define empty target run: either good vacuum in the cell and chamber or same pressure in cell as in the target chamber (when hydrogen is flowing).
     • Need to define the type and number of solid targets. One solid target would be the easiest configuation.
     • Can we make the target cell diameter bigger? This would help the pressure inside the cell. Main unknown: the beam halo extension. FX is checking with Arne for a conservative and realistic estimate.
     • How far away from the cell can be accept heavy material? Answer will depend again on the beam halo.
     • Need to provide design and support structure for the pumps and chambers. Mehdi will ask Gary Swift if he can help.
  2. All: Need to provide Josh answers within two weeks.
  3. Mehdi: Will ask Huntington for the software of the 3D positioner.
  4. Zhihong: Will talk to Carlos Ayerbe about DAQ availability.

• Talks:
  1. Dead Areas on GEM by Chao Peng (12 pages)
  2. Update Simulation for Adding a Tube by Li Ye (16 pages)

March 28

• Participants: Alexander, Ashot, Chao, Dipangkar, Francois-Xavier, Li, Mehdi and Zhihong

• Minutes:
  1. Li: (See slide below) From his study, GEM generate low background. Also vacuum box with a pipe that runs through HyCal is a better solution than a single thin window. Need confirmation of this result with Moller events. Simulation is ongoing.
  2. Ashot presented a plot of Q² resolution vs angle with 100 μm beam spot, 2 mm Al window and vertex uniformly distributed along the z axis (4cm total). 0.3 mm resolution tracking detector would be desirable.
  3. Mehdi: Working with Gary Swift from TUNL on the vacuum box. Will work with Bob Michael to get his feedback on the design.

• Talks:
  1. Preliminary simulation for Scintillator Fiber Tracker (SFT) by Chao Peng (10 pages)
  2. GEM detector simulation by Li Ye (7 pages)
  3. Vacuum Box Design and Background Simulation by Li Ye (13 pages)
  4. A plot for the Q2 resolution vs theta by Ashot Gasparian (1 page)

March 14

• Participants: Alexander, Ashot, Chao, Dipangkar, Francois-Xavier, Li, Mahbub, Mehdi and Zhihong

• Minutes:
  1. Zhihong: Almost ready to test the fibers (Power supplies, NIM crate, Fastbus, fibers and SiPMT are on site). Asked the Jlab machine shop to produce fiber/SiPM connectors. Looking for a black box (~2m long) for a light yield test. SiPM will be from HallB and different type of fiber form HallC. An cost estimate of the detector for PRad is ~$80k + overhead and without DAQ.
  2. Dipangkar will talk to the NorthWestern group about MaPMT (16 pixels) from D0, Ashot will ask Bogdan for DAQ and other items.
  3. Li: Fixed the bug in his code. Results are shown in the presentation below. He will redo the study with an energy deposit cut in HyCal and no angle cut, similar to a level 1 trigger.

• Talks:
  1. Update background simulation for Vacuum box window by Li Ye (10 pages)

March 7

• Participants: Alexander, Ashot, Chao, Li, Mahbub, Mehdi and Zhihong

• Minutes:
  1. Chao and Li picked up part of the 3D positionner at NSU. One box was to big to fit in their car. They will complete the job by Tuesday.
  2. Ashot: talked to Bob and Volker, PRad is on the same footing as HPS as long as we passed the March 21st internal review with JLab management. According to Arne, the beam quality should be OK for 1-2GeV.
  3. Chao will look into the background rates due to the collimator
  4. Li will cross check his results with Chao's code to understand why the rates get smaller when the vacuum box window gets thicker. May be due to statistic.

• Talks:
  1. Background study with collimators by Chao Peng (10 pages)
  2. Background simulation for Vacuum box window by Li Ye (9 pages)

February 28

• Minutes:
  1. Target Chambers: Mahbub and Mehdi sent the initialed drawings back to Pfeiffer. Construction will take ~8-10 weeks. Little issue with an extra $200 shipping cost. Will ask for a separate bill in order to avoid redoing a new order at NSU.
  2. Alignment System: Delivered Monday Feb. 24th. Vina will bring it to Jlab.
  3. Coordinate Detector: Zhihong has been award of an $11k JSA Postdoctoral Fellowship. Will be used towards a XY position detector prototype (scintillating fiber). He will give a talk at the next CLAS meeting on Monday March 3rd. Seems that this type of detector is the best option (no need to be as precise as GEM (see Chao's studies), the UVA group is already very busy with SuperBigBite and SoLID) however the cost needs to be evaluated. Zhihong will contact detector engineers at Jlab as wells as at Saint Gobain. Will need help from Jlab for the electronic.
  4. Ahsot, FX and Mahbub will work on the halo monitor.

February 21

• Talks:
  1. Background study with collimators by Chao Peng (9 pages)

February 14

• Talks:
  1. Radius extraction 2 by Chao Peng (15 pages)
  2. He4 Bag Simulation by Li Ye (6 pages)
  3. On the possibility to reconstruct the event vertex by Alexander Gramolin (8 pages)

February 7

• Talks:
  1. Radius extraction by Chao Peng (9 pages)

January 31

• Talks:
  1. GEM Detector Simulation by Li Ye (7 pages)
  2. A simple study of the angular and Q² resolutions by Alexander Gramolin (5 pages)

January 24

• Talks:
  1. Q² resolution by Chao Peng (2 pages)

January 17

• Talks:
  1. Tracking and Q² resolution by Chao Peng (12 pages)