Apr 26, 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; JLab Phone in CC L207 is 757-269-7084
• Athens Phone: in Christina's office is 011-30-210-727-6947
• Regina Phone: in LB228 is 306-585-4204
• 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: Review if cross talk experience from other detectors is relevant to this geometry and, if needed, suggest test/simulations to investigate.
2. Simulation
   • Need to study the reconstruction efficiency.
   • Investigate timing resolution as it impacts delta_theta. Start with understanding of resolution at 90 deg. Ongoing studies.
   • Check timing resolution at 90 deg compared to beam test
   • Check inefficiencies compared to previous studies by Mihajlo.
3. SiPMs
   • Re-measure original SiPM sample to verify rates are in fact lower for new arrays Measured but not yet analyzed.

Tentative Agenda

1. Announcements
2. Review of Action Items
3. Monitoring
4. FCAL
   1. Construction Status: mechanical, bases
   2. Photos of Base Testing
5. BCAL
   1. Construction Status: builds, fibre QA
6. Collaboration Meeting Presentations
   • Tuesday 14:30 Session IVa (120) --- Calorimetry - (Organizer: Matt Shepherd) - Chair:
     • 14:30 (30) ---
     • 15:00 (30) ---
     • 15:30 (30) ---
     • 16:00 (30) ---
7. Simulations
   • BCAL Segmentation (David)
8. SiPM First Article (Yi)
9. Timing and rate measurements of SiPMs (Baturin)
10. Any other business

Minutes

Attending: Ivan Tolstukhin, John, David, Tim, Yi, Beni, Eugene, Sasha, Vitaly Baturin (JLab); Zisis, Andrei (UofR); Matt, (Alex to say hello) (IU); Will, Serguei (USM).

1. Announcements
   • Hall D has posted a position for a Hall D scientist. A second position will open next fiscal year.
2. Review of Action Items
3. Monitoring
   • A small contract to fabricate 2 control boards and 80 LED boards has been placed with Athens.
   • The APP for the larger contract for monitoring of Fcal and Bcal is getting signatures
4. FCAL
   1. First shipment
      • 13 crates shipped to JLab. They arrived safely. Elton and Beni inspected the boxes, but opened only two. They glass blocks were nicely packed and in apparent good condition.
      • Discussion: How much inspection should be done before actual stacking the glass in the hall. The suggestion was to unpack one box completely. Matt suggested unwrapping only the end and checking the glass head-on. The mylar wrapping is delicate and dust is our enemy.
      • Should decide how extensive the checking of the crates and their contents should be.
   2. Prototype support structure
      • John has put together 4-5 rows of blocks. Stacking has not as even as hoped. Ongoing study to improve the procedure.
   3. Photos of Base Testing
      • 1/4 scale setup includes 4 CAEN-ethernet bus loads. At the moment only 2 out of 500 boards are not operational. Testing continues, as humidity increases they will be checked carefully.
      • Hovanes has been in contact with Matt and they can provide him CAEN controllers to test slow control setup.
5. BCAL
   1. Construction Status: builds, fibre QA
      • Construction nominal: Will complete modules 35 and 36 next week.
      • Will ship modules 29-32 next week (shipment #8)
6. Collaboration Meeting Presentations
   • Request one additional 30 min slot and that the cal session be moved to first session of the morning to allow Athens participation.
   • Tuesday 14:30 Session IVa (120) --- Calorimetry - (Organizer: Matt Shepherd) - Chair:
     • 14:30 (15) --- Fcal construction status (Matt)
     • 14:45 (15) --- Bcal construction status (Zisis)
     • 15:00 (30) --- Monitoring of Fcal and Bcal (Christina)
     • 15:30 (30) --- SiPM First Article Testing (Yi)
     • 16:00 (30) --- SiPM production testing at USM (Will)
     • 16:30 (30) --- Cooling/Bias Compensation/Electronics (Elton?)
7. Simulations
   • BCAL Segmentation (David)
   • Note: Photons were generated flat in Energy (0-4 GeV) and angle (10-110 deg)
   • Substantial discussion following David's talk. The behavior of the efficiency (last plot) is not understood as a function of angle or the differences between the different algorithms.
   • Eugene: If resolutions require this, one could consider adding one more ring, but a clear justification for cost is needed.
8. SiPM First Article (Yi)
   • Unfortunately this report was not presented for lack of time.
9. Timing and rate measurements of SiPMs (Baturin)
   • Vitaly showed preliminary results for the timing resolution of SiPM sensors: 1x1 mm2, 3x3 mm2 and one array 16 3x3 mm2.
   • Preliminary results show that the array operates satisfactorily to 1 MHz, but the 3x3 unit performance deteriorates above 0.1 MHz.
   • Caution: The preamplifier boards are being replaced with newer designs to handle the rate.
10. Any other business