April 4, 2008 Calorimetry

From GlueXWiki
Revision as of 14:38, 4 April 2008 by Elton (Talk | contribs) (Minutes)

Jump to: navigation, search

Connection

  • The meeting will be held at 1:00 pm ET (11:00 am MST)
  • 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 Schedule
    • Criteria for selecting SiPM type
    • Testing procedures
      • What
      • Where
  3. Fiber Specifications
    • Response of Kuraray and St. Gobain to the request to JLab sources sought / do we need more samples?
    • 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
  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

Minutes

Attending: UR Zisis, George, Andrei, JLab: Fernando, Tim, Jim, Stewart, Elke, Elton, Carl, Eugene.

  1. Review Options for Working Group Meeting Time
    • Next meeting will be Tuesday 10:30 ET April 15.
  2. SiPMs Schedule
    • Criteria for selecting SiPM type.
    • Shipping of SiPMs is becoming problematic. Elke suggested paying for shipping directly to Regina. 2 units to Regina of each type, 3 units to JLab of each type.
    • 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. Kuraray and St. Gabain have sent in (confidential) responses and will be provided to members of the evaluation board (Elton, Carl, Stepan Stepanyan, George).
      • do we need more samples?, they could be provided if requested through the request for sources sought
    • Polishing of fibers:
      • Regina has had difficulty obtaining high quality fiber surfaces. Carl has had experience in this area and send around specific information on the companies and procedure he uses.
    • How to specify a) Fiber color/spectrum and b) light output are the two main issues to complete the specification. Some of the information received in the sources sought might be used to firm up the specification.
    • There is an automatic fiber cutter which they have borrowed for cutting some fibers and does a wonderful job. They would like to purchase one for long-term use.
    • JLab Tests (Carl)
  4. Review of Action Item Tracker
    • Fabrication plan and QA requires close consultation with Alberta on this plan. Elke will see Jim Pinfold next week and review possible plans for use of Alberta facilities.
  5. FCAL Update
    • A few plots that show typical FADC response and time resolution that migh be achieved (Mihajlo)
      • Mihajlo showed preliminary results on a study to look at the resolution of extracting the leading edge of pmt pulses in the FCAL.
  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