Jun 2, 2011 SiPM Electrical and Cooling

Action Items from previous meetings

1. Check impact of material at low end of readout, both in the tubes for cooling fluid but also in the Cu cooling plate. Need to check effect on particle trajectories.
2. Jim will order the mechanical cover so that the Lemo connections can be checked for rigidity

Tentative Agenda

1. Announcements
2. Action Items
3. Schedule, reporting, and manpower (Elton)
4. SiPM testing (Carl and Yi)
5. Mechanical (Jim)
6. Mechanical drawings (Chuck)
7. Geometry (Elton)
8. Temperature compensation (Jack)
9. Preamp-summing (Fernando)

Minutes

Attending: Jack, Chris, Jim, Ivan, Yi, Elton, Carl, Chuck

1. Announcements
2. Action Items
   • Beni is implementing the new readout structure into the physics simulation to check efficiencies
3. Schedule, reporting, and manpower (Elton)
   • No progress in May. Need to complete electrical testing soon
4. SiPM testing (Carl)
   • PicoQuant will provide a Fast Blue LED/laser system to Carl on 3 week loan for evaluation. May be used for production testing based on evaluation.
   • White diffuse film with reflectance curve has been ordered to be used for uniform illumination in production setup.
   • No feedback from Hamamatsu on first article report
5. SiPM testing (Yi and Ivan)
   • Working on Labview program for temp compensation test
   • Building a black box for testing timing properties of SiPMs (for PS or tagger). Test to be able to set two pulses with adjustable timing delay to measure pulse recovery time.
   • Optic components have arrived.
   • Asked Carl if they could use his calibrated photodiode. This will be fine, but they may also wish to purchase one for our own setup.
6. Production Testing (discussion)
   • Will need to firm up test plan next week, including inventory of parts required
   • Likely use CAEN integrating ADCs, 16 SiPMs at one time (256 channels).
   • Need to verify lab inventory of ADCs
   • Need to decide on cable connections, which may impact electronics design. Will need to talk to Fernando about what board to use next week.
   • Jack: SamTech has ribbon cable assemblies that may be useful. Otherwise we will need to purchase coax cables and cable converters to multipin connectors.
7. Mechanical (Jim)
   • Pieces of prototype pieces are in receiving.
   • Tim will assign someone to put the prototype together
   • Still need to order the new cover to test with this prototype.
8. Mechanical drawings (Chuck)
   • Light guide drawings with new symmetric configuration are being checked
9. Geometry (Elton)
   • New geometry is being implemented in the light collection program. Should have results by next week.
10. Temperature compensation (Jack)
    • Jack will use the board that Fernando tested to check the bias circuitry. Response to changing temperature will be tested once a box is completed that allows changing temperatures.
    • Black box with temperature settings will be used for testing the bias compensation circuit.
    • Yi and Ivan promised software for next week.
11. Preamp-summing (Fernando)
    • Fernando had a first look at the preamp-summing prototype and sent an e-mail. Circuits worked well, but the signal rise time was about 24 ns, exceeding our requirements. Chris has shortened some of the cable connections to see if they reduce the rise time. Jim will send information about other (larger) cable options, consistent with layout, which might also help reduce rise time.
    • Chris has completed the interconnect board (with Lemo connectors). Fernando will check it next week
    • Chris has also completed the dummy heat generation board to be used with the mechanical prototype, and can be incorporated into the mechanical test.