Jan 5, 2011 SiPM Electrical and Cooling

Tentative Agenda

1. Announcements
2. Action Items
3. Schedule, reporting, and manpower (Elton)
4. SiPM production testing (everyone)
5. Mechanical assembly (Scot)
6. Mechanical (Jim)
7. Mechanical drawings (Chuck)
8. Temperature compensation (Jack)
9. Preamp-summing (Fernando/Chris)

1. SiPM testing (Ivan)

Minutes

Attending: Jack, Carl, Chris, Alex, Ivan, Tom, Jim, Yi, Elton, Eugene, (Note: Scot is out on sick leave till 17)

1. Announcements
2. Action Items
3. Schedule, reporting, and manpower (Elton)
   • No updates since last year
4. SiPM production testing (everyone)
   1. Electronics (Chris)
      • One board is nearly complete. The connectors will be mounted on the front, but Carl does not believe this will lead to any interferences.
      • The board should be completed tomorrow. Fernando should concur that cables are ok to go ahead and order the ones for the other boards.
      • Will install in setup when it is ready.
   2. Optical (Carl)
      • Illumination varies by up to 5% over the sensor area. Has ordered parts to be able adjust tilt of plate to improve the uniformity. There will likely be position dependent corrections on the extracted parameters of the sensors.
   3. Mechanical (Jim)
      • Tooling for insertion/extraction may need modifications for the test setup
   4. Software (Yi)
      • Readout has been tested with pedestals and works. Presently operation is in "expert" mode. Will need to write down procedures and make it routine.
   5. Integration
      • Once the test setup is complete, Carl and Yi will work through the setup to see how it works, show it to Elton, and then to Tom. Procedures will be improved by iteration. Personnel to test the sensors will be identified from students (Eugene) or the technical pool (Tom).
5. Mechanical (Jim)
   • A few mechanical pieces are missing to complete gluing and assembly of mini-Bcal. Jim should order these.
   • Some discussion of the schedule for monitoring boards. Elton said that they will probably be delivered by April, but not in time to include during the light guide gluing procedure. Jim noted that at least one column could be instrumented after the fact, and other columns might be able to be added also.
6. Mechanical drawings (Chuck)
7. Temperature compensation (Jack)
   • Presented study of determining nominal parameters for bias circuit. Conclusion is that little is gained by trying to compensate for increased leakage currents after irradiation. The components will be selected assuming a leakage current of 1 microA.
8. Preamp-summing (Fernando/Chris)
   • The wedge boards have been received. Expecting quote for population. 5 day turn-around time is expected
   • U-boards (and any other parts for prototype assembly) need to be ordered.

1. SiPM testing (Ivan)
   • Ivan presented results on the SiPM measurements, which lead to interesting discussion. The slides are available on the group disk.