Nov 18, 2010 Readout

Teleconference Time: 11:00 a.m. EST

• ESNET 8542553 and EVO session
• Phone in CC L207 is 757-269-7084
• Phone in the Regina Videoconference Suite is 306-585-4204
• Phone:
  • +1-800-377-8846 : US
  • +1-888-276-7715 : Canada
  • +1-302-709-8424 : International
  • then enter participant code: 77438230# (remember the "#"). Phone connection only upon request.

Items for followup from previous meeting

1. Collect this information of testing (including goals and setup) on the wiki for ease of presenting information. (USM)
2. Resolution including summing SiPMs (IU)
3. Elton to check availability of spare SiPM array to lend to USM
4. Elton to investigate the options for transfering laser to UofR for future tests

Tentative Agenda

1. Announcements
2. Review of Action Items
3. Update - USM
   • Schedule for contract. See Timeline
4. SiPM update
   • Communications with Hamamatsu (Carl)
   • Preparations for test at Regina (George)
5. Electronics/cooling (Fernando)
6. Geometry and light guides
7. Monitoring system
8. Simulation runs

Minutes

Attendees: Will (USM); Elton, Beni, Yi, Fernando, Chuck, Tim (JLab), Carl, Drew, Jack McKisson (JLab detector group); Zisis, Andrei, George (UofR); George, Christina (Athens)

1. Announcements
2. Review of Action Items
   • JLab will prepare a SiPM array to ship to USM.
   • Elton will contact JLab property vis-a-vis transfer of laser to UofR.
3. Update - USM
   • Technical progress
   • Small CNC machine procured sometime ago. A second small CNC machine procured and arrived. A large CNC machine ordered.
   • New machines can be used to make prototypes for testing on the Baby Bcal.
   • More space obtained, which will be used for measuring SiPM response
   • Most all components have arrived to complete the SiPM testing board
   • Awaiting some parts for dark box. Cu cooling plate not yet arrived, and this one requires considerable machining of slots for SiPM connections
4. USM Contract
   • Schedule for contract. See Timeline.
   • Elton described the schedule. The precise time constraints related to putting a contract into place with USM are getting tight. We need to move forward agressively to make this happen.
   • Will reviewed four items discussed for SOW: SiPM testing, light guide fabrication, producing and/or testing electronic boards, testing disc boards. The first two items are much better defined. It was suggested that the last two items might have considerable work done at or near JLab.
   • In order to converge, Elton suggested to include only the first two items in the contract.
   • Will to produced a SOW based on the first two items
   • Elton to produce a schedule for the project. Both documents should be iterated on a short time scale.
   • Zisis: Need to summarize this information in a location that is accessible to everyone.
5. Light guides
   • Tim asked whether USM would produce suffient "first-article" light guides for a complete Bcal wedge. This needs to be discussed further in relation to the USM contract.
   • Chuck has produced drawings of the 20 types of trapezoidal guides. Elton will put these on the portal for reference. See GlueX-doc-1642.
6. SiPM update from IEEE
   • Communications with Hamamatsu (Carl). Carl, Drew and Jack participated in the IEEE and had a chance to communicate with Hamamatsu and SensL regarding SiPMs. Carl summarized.
   • Will collect documents of interest to GlueX and post on portal. In particular there have been some studies on temperature dependence of SiPMs that might be of interest.
   • Hamamatsu is coming out with new series of prototype detectors, including stackagle arrays "lego" style, and some with improved timing for large areas
   • Hamamatsu believes that radiation resistance (especially to neutrons) sensors could be produced. They believe that the radiation sensitivity is not in the wafer itself, but rather due to surface effects i the passivation(?) and/or encapsulation. They make samples available to JLab for testing. It is unclear whether improved units could be delived on the schedule for the recent contract.
   • Jack suggested that we might wish to ask Hamamatsu to provide the SiPM first article samples from several wafers. George: it is likely that 80 arrays will come from various wafers anyway. We can bring this up during the visit by Hamamatsu in early Dec.
   • One issue raised by Hamamatsu concerned the split of sensors between JLab and Chile. This will be discussed when Hamamatsu visits. We may wish to include Will (USM) in a phone conference while they are here.
   • SensL: is improving their product, using new 8" wafers. Dark rate reduced by 6, and "improved DC response" by 2.5 (not clear how this translates into PDE). Product not yet available but should be available next year.
7. First Article Testing of SiPMs
   • JLab is getting prepared to test the first-article SiPM units when they arrive. However, contributions from other groups for broader scrutiny is welcome.
   • Current setup probably adequate, but requires upgrade to DAQ for mass testing of sensors
   • Also need to control temperature during testing. Fernando: Note that strickly for the first-article tests, we need only testing at room temperature. Testing at other temperatures are necessary only for our own information and design of final system.
   • Fernando: 16-channel individual readout electronics unit will be designed by mid-Dec and available by mid Jan.
   • Jack McKisson: Designing circuits for bias control and temperature feedback. Will require testing with summed SiPM outputs. Final testing will require full readout including mechanical temperature stabilization and housing.
   • Tim: Mechanical and cooling design: Looked at using 40deg F chilled watter in heat exchanger to be used with closed circuit loop with coolant. Will assing an engineer to take over this project. Likely coolant will be some kind of alcohol, so that it can be used below freezing. Temperature range of system will be 0-60 deg C. Operation of SiPM will be approximately between 5 and 30 deg C. Fernando noted that the coolant for the FDC (fluorinent) might be useful.
8. Preparations for test at Regina (George)
   • Redesign of mechanical assembly at Regina is underway. It will be able to accomodate both Hamamatsu and Sensl units. Spring loaded holder for sensor has been designed and will be used to illuminate sensors with either LED or laser in a surface scan.
   • New graduate student has been tasked with these tests. Kathryn helped setup the system and will be back later this year to complete testing.
   • Testing of first articles can be done with LEDs and 90Sr sources, and the laser if fixed by that time.