Jan 22,2013 Readout

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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 757-269-6460 (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. Monitoring
    • Work out shipping details (Elton and Christina) Two packages shipped, should arrive today.
  2. Light guides
    • Review shipping procedures (Will) E-mail from Iñaki describes a new improved packing scheme.
  3. SiPMs
    • Recent photos of 17 scratched SiPMs will be uploaded to the data base.
    • Provide a histogram of capacitances of all MPPCs (Orlando) See Capacitance temperature

Presentations from recent meetings

Tentative Agenda

  1. Announcements
  2. Collaboration Meeting
    1. Thursday February 21, 2013
    2. 10:55 Session Ic (100) --- Calorimetry - (Organizer: Matt Shepherd) - Chair:
  3. Review of Action Items
  4. Monitoring
  5. Update from USM
  6. Status of gluing light guides at JLab
  7. Status of testing at Regina
  8. Simulations
  9. Beam Tests, Cosmics
  10. Other


Attending: Elton, Beni, Yi, Fernando, David (JLab); Zisis, Andrei (UofR); Christina, George (Athens); Hayk, Orlando (USM).

  1. Announcements
  2. Collaboration Meeting
    1. Thursday February 21, 2013
    2. 10:55 Session Ic (100) --- Calorimetry - (Organizer: Matt Shepherd) - Chair:
    3. Zisis: suggestion to start the session earlier in the day to allow Athens to participate. (Could interchange session with mechanical or move to the next day)
    4. Suggested topics are
      • Bcal production including testing
      • Fcal Update including lead glass stacking
      • Summary of SiPM testing (USM)
      • Monitoring (Bcal production and Fcal status)
  3. Review of Action Items
  4. Monitoring
    • Two boxes with Bcal monitoring boards and controllers have been shipped and should be delivered today.
    • Tests are ongoing on Fcal with blasting plexiglass. Will be reported at the calorimetry meeting next week.
  5. Update from USM
    • Checking of 75 failed SiPMs is ongoing. Report next week
    • Photographic images are being analyzed automatically and results will be reported next week.
    • No update on the status of 360 units in customs.
  6. Status of gluing light guides at JLab
    1. Media:Gluing1.JPG Upstream end of module 45 before gluing.
      • Elton pointed out that several "white" fibers appear on the face of the Bcal. Inspection shows that transmitted light shows darkened fibers. This is on module 45
      • Zisis: Will check the high-resolution photos of this module to check whether this problem was visible before.
    2. Media:Gluing2.JPG Upstream end of module 45 without flash.
      • Gluing ten light guides at a time is working relatively well. We started with the goal of obscuring less than 8 fibers (2%) with bubbles. We will see how easily a goal of 1% can be achieved.
    3. Media:P1010007.JPG LED boards mounted onto first column (upstream) module 45
      • We have not yet worked out the final strategy for attaching the LED boards to the light guide.
      • Initial use of UV curing glue (light shining only from the end) resulted in several boards coming off when the flex cable was attached. We secured them with crazy (or super) glue, but there is concern that this will lead to crazing long term. Several people expressed concerns about using crazy glue.
      • Another alternative was considered: Using double-sided industrial tape. We tried on type of this tape, which adhered tightly to the tedlar, but not the light guide. That option did not keep the LEDs securely into the hole.
      • We have gone back to the UV curing glue and shined light from the end and also through the downstream end of the pocket. This seems to hole the boards in place. We have also placed a strip of Kevlar tape over the top to secure it to the tedlar (see next photo)
      • Zisis: Could consider heat shrink tubing around the guide. Heating the tubing could affect the light guide. There is also "stretch netting" that could be useful for mechanical constraint.
      • Fernando: acrylic tapes may loose their adhesion over time, especially in a radiation environment; crazy glue (and fumes afterwards) can react with plastics; should further investigate the time to cure the UV glue.
    4. Media:Gluing4.JPG All columns glued on to upstream of module 45.
    5. (Note: added after the meeting) Media:Gluing5.JPG Downstream end of module 45 with 2 columns glued. Shown is the monitoring string secured with Kapton tape
  7. Bcal Electronic boards (Fernando)
    • All jumper maps are complete and ready to specify location of jumpers
    • Nick and Chris have tested more than half of the board and they all meet specifications
    • The rest of the boards should be tested by the end of the month
    • Mechanical parts for the readout have been received. They still need to be sent out to be anodized.
    • Pre-assembly of the readout assemblies will begin soon in preparation for complete assembly including electronic boards.
  8. Status of testing at Regina
  9. Simulations
    • Status of Sampling Fraction Study (Andrei)
    • Sampling studies have been completed. Andrei went over the results
    • The parameterization of the constants reproduces the performance of the fine-grained calorimeter very well, except for hight energy particles at large angles. This kinematics is not very likely, so the discrepancy in this location may be acceptable.
    • Request to David: verify thresholds and consider practical packaging of data including possible interpolation.
    • Elton: This work will be the basis of the calorimeter simulation, so it should be written up into a document summarizing the assumptions that were made, the procedure and the results.
  10. Beam Tests, Cosmics
  11. Other