Mar 17, 2011 Calorimetry

Teleconference Time: 11:00 a.m. EST

• ESNET (Number is 8542553) and EVO session (GlueX Calorimetry meeting room)
• JLab Phone: in CC F326 is 757-269-6337
• Regina Phone: in LB228 is 306-585-4204
• Athens Phone: in Christina's office is 011-30-210-727-6947
• Phone connection only upon request.
  • +1-866-740-1260 : US+Canada
  • +1-303-248-0285 : International
  • then enter participant code: 3421244# (remember the "#").
  • or www.readytalk.com (and code without the #)

Items for followup from previous meeting(s)

1. Monitoring
   • Fcal: check cross talk of calibration inputs across modules.
2. Fcal construction
   • JLab to provide shipping guidelines to Matt

Tentative Agenda

1. Announcements
   • Starting next week, we will move the Bcal Readout meeting and Cal Working Group meetings to TUESDAY 11:00
2. Review of Action Items
3. Calibration
4. BCAL
   1. Construction Status: builds, fibre QA
   2. First article testing (Yi) Result Page
5. FCAL
   1. Construction Status: mechanical, bases - no report
   2. Drawings for Fcal structure (Tim) Sketches for comments on FCAL structure
6. Simulations
   1. Readout segmentation (Andrei)

Minutes

Attending:Elton, Yi, Eugene, David, Tim, Beni, John (JLab); Zisis, Andrei (UofR); Will (USM); Christina (Athens),

1. Announcements
   • Starting next week, we will move the Bcal Readout meeting and Cal Working Group meetings to TUESDAY 11:00
2. Review of Action Items
3. Calibration
   1. Concept for Fcal settled
   2. Discussions on Bcal option underway
      • Will present concept to this group at next meeting (Mar 29)
      • Modifications include daisy-chaining LED boards together
      • Use CAN bus to communicate with control boards
      • Consideration for optimum placement of LED boards on detector, including possibly attaching 2 fibers to each LED
      • UofR will come up with some sketches that can be passed on to our designers to verify geometry
4. BCAL
   1. Construction Status: builds, fibre QA
      • Construction proceeding well. Modules 33 and 34 are about 30-40% complete.
      • Machining of Module 26 started Mar 15. Start delayed to allow large job from Alabama to be completed at Ross Machining.
      • Schedule for shipping will be updated once two modules are finished. Expect two shipments, one at the beginning of April, one at the end.
   2. First article testing (Yi) Result Page
      • Received 80 first-article samples from Hamamatsu last Wed.
      • To date 25 units have been tested, but results are still under evaluation
      • Test use a calibrated LED and five light settings using a neutral density filter.
      • Gain measurements are relative, absolute calibration not yet completed.
      • Rates normalized to 25deg C (where Hamamatsu specifies the units). Dark rates are about 16 MHz/array, about 4 times lower than original samples. Eugene would like to know what has changed in the fabrication process.
      • Tim: Have any dimensional checks been made?
      • Zisis: Suggest that Yi add quick progress checklist on the wiki for easy reference of measurement status.
5. FCAL
   1. Construction Status: mechanical, bases - no report
   2. Drawings for Fcal structure (Tim) Sketches for comments on FCAL structure
   • Following the last meeting, Tim, Wayne, Matt and John met to go over details
   1. • Decision to stiffen support structure. Tim and Wayne have had discussions with designers of the support frame for the JLab Big-Cal support structure, who provided feedback to our concept
      • IU will build a prototype to test the layout with two rows of 20 bars, which will take 4 weeks.
      • Fabrication of parts will follow after incorporating feedback from the prototype.
6. Simulations
   1. Readout segmentation (Andrei)