Jun 26, 2012 Readout

Teleconference Time: 11:00 a.m. EST

• ESNET (Number is 8542553) and EVO session (GlueX Calorimetry meeting room)
• Phone connection only upon request.
  • +1-866-740-1260 : US and Canada
  • +1-303-248-0285 : International
  • then use participant code: 3421244# (the # is needed when using the phone)
  • OR from www.readytalk.com type access code 3421244 into "join a meeting" without the # (you need java plugin)

Participant Direct Lines

• JLab Phone: in CC F326 is 757-269-6337 (usual room)
• JLab Phone in CC L207 is 757-269-7084
• Phone in the Regina Videoconference Suite is 306-585-4204
• Athens Phone: in Christina's office is 011-30-210-727-6947

Items for followup from previous meeting

1. SiPMs
   • Investigate the optimum overbias setting for the SiPMs (Serguei and Orlando)

Tentative Agenda

1. Announcements
2. Review of Action Items
3. Update from Athens: monitoring
4. Update from USM
   • SiPM Update (Javiera)
   • Light guides
5. Status of testing at JLab
   1. Hall-D ELOG.
6. Status of work at Regina
   1. BCAL Beam Tests 2012: Analysis & Simulations (Andrei & Irina)
   2. BCAL Cosmics at Regina
7. Other

Minutes

Attending: Elton, Beni, David, John, Ben, Yi, Tim (Jlab); Will, Javiera, Orlando, Iñaki (USM); Zisis, Andrei (UofR); Christina, George, Stratos (Athens)

1. Announcements
   • Students (and Zisis) from UofR arrive on July 9
2. Review of Action Items
3. Update from Athens: monitoring
   1. SiPMs for testing. One in regular mail (needs to be tracked down) and 3 to be hand-carried by George
   2. Orders
      • Requests have been made, but little response.
4. Update from USM
   1. SiPM Update (Javiera)
      • Fourth shipment from Hamamatsu arrived on June 20
      • All units from first three shipments completed in stage 3. Starting to test 4th shipment
      • 265 units PDE measured in stage 2. 15 more required to complete all measurements
      • Zisis: request a summary table from Javiera during update.
   2. Discussion on what information must be provided on the tested SiPMs
      • Will: Suggestion to provide a dump of the data base for each shipment delivered. Note that this is simply a snapshot in time that can change when analyses are updated.
      • Consider various options for concise summaries also.
      • Yi: JLab has three tables a) specification and Hamamatsu data b) All run information and raw data c) summary of measurements
      • Failed units: one from USM with a dead channel, one from JLab that fails to meet one of the specifications.
   3. Contract and pulse shape
      • Pulse shape measurements are dominated by the response of the JLab preamps. Is is worth doing these systematically
      • Elton: Checking signals on scope can be very informative.
   4. Revisiting the dark current measurements (Orlando)
      • The dark current measurements seem to be low. Data have been taken with the oscilloscope to cross check the measurements (in progress).
   5. Light guides
      • Internal cracks (barely visible) developed in 400 of the type A light guides. The cracks are very small, but due to uncertainties of how they might develop, they are being fabricated again.
      • Cracks happened during milling. Presumably this was due to locally produced heat during machining. The lubrication is a mixture of lubricant and coolant, not water, automatic feed from the machine.
      • The cutting tool was changed and resolved this issue. It does not seem to be due the material.
      • John: How many guides have been machined since the tool and process were fixed? Over 300.
      • There have been some delays due to machine repairs
      • Waiting for repairs, the process has been optimized and time per piece reduce by 20%.
      • Status: 50% of guides are machined, 6% have polishing complete. All jigs have been complete, but guides HJK and A still need to be machined.
      • Shipping: Expect the first shipment second week in July.
5. Status of testing at JLab
   1. Hall-D ELOG.
      • Inventory shown in log book entry. Many units are dispersed around the collaboration and test setups need to evaluated in relation to number of spares that might be available.
      • Will has sent an inquiry to Hamamatsu to find out if we can order additional SiPMs at this time. No response yet.
6. Status of work at Regina
   1. BCAL Beam Tests 2012: Analysis & Simulations (Andrei & Irina)
      • Simulation shows a 10% resolution at 5 deg and 1.9 GeV. Data shows approximately 13% resolution. Analysis is ongoing.
   2. BCAL Cosmics at Regina
      • Setup is being updated and is almost ready to go.
      • Students are getting trained in the process and preparing to come to JLab, They will be at the lab on July 10. They will need ODH and Rad Worker I training.
7. Other