April 15, 2008 Calorimetry

Connection

• The meeting will be held at 10:30 am ET
• Phone:
  • +1-800-377-8846 : US
  • +1-888-276-7715 : Canada
  • +1-302-709-8424 : International
  • then enter participant code: 39527048# (remember the "#")

Reference Documents

1. Previous minutes: March 21, 2008 Calorimetry
2. Schedule, Tracker and Drawings (gluex pass)
3. Schedule

Tentative Agenda

1. Review Options for Working Group Meeting Time
2. SiPMs
   • Phone conference yesterday. Divided shipments of 1 mm2 A20HD and A35HD and 3 mm2 A20HD units shipped to UofR and JLab. 3mm2 A35HD units delayed by 4-6 weeks.
   • Testing to be conducted upon receipt:
   • UR tests
     1. IV curves
     2. Scanning SiPMs for uniformity. Current illumination is 1mm diameter, but improving setup to 0.25 mm diameter to allow for finer scans.
     3. Use coupling to fiber array to measure light yield and normalized to the number of photoelectrons. [Array is about 2x1.8x25 cm3. On one side the fibers are flared out and coupled to a Winston Cone guide.
   • JLab tests, use optical setup using LEDs
     1. IV curve
     2. Linearity of response
     3. Relative gain
     4. Dark rate
     5. Timing characteristics. [Notes from George: timing response of newer glass arrays show rise times of about 10 ns, and contained in a 70-75]
     6. Later, not in initial tests: temperature dependence of units.
3. Fiber Specifications
   • Response of Kuraray and St. Gobain to the request to JLab sources sought / do we need more samples?
   • Summary of fiber spectra analysis (Alex) [1]
   • How to specify a) Fiber color/spectrum and b) light output
   • JLab Tests (Carl)
4. Review of Action Item Tracker
   • Fabrication plan and QA /visit to Alberta?
5. FCAL Update
   • A few plots that show typical FADC response and time resolution that migh be achieved (Mihajlo)
6. BCAL Update
7. SiPm gain non-uniformities and energy resolution (Richard)
8. Calibration Update / Discussion (Athens) - postponed to next meeting
   • Goals for calibration
   • Deployment in various subsystems
9. Any other business