sPHENIX discussion of electronics

[Eric Mannel <mannel AT bnl.gov>]

Folks-

I am a little slow getting a summary out on last weeks SiPM testing discussion in the CalElc and HCal meetings:

1. Hamamatsu has aggreed that all future trays will have the same Vop bin ranges.
2. There was some discussion about the exact definition if the Vop bins that needs further understanding.  Our test results may shed some light on that.
   
3. Debrecen personnel will arrive around April 25 to start setting up the test stand at UofM.
4. Testing will start with one tray per day and ramp up to multiple trays depending on number of devices/tray
5. The device ordering in trays will remain as shipped by Hamamatsu, but test results will allow us to look at alternative options for binning and tray assignments.
6. The HCal group wants to have thier devices re-tested prior to assembly.
7. The first device that are required are for HCal, so we should focus verification of Vop for trays that will be assigned to HCal production.  Based on Hamamatsu documentation we should identify trays out of the first 3 deliveries for HCal
   
8. The EMCal assembly, while not as critical, needs to move forward by mid-summer so we will have to have have or order 23K devices tested by first of July.
9. We will work with the assembly house to track the SiPM trays with assembled boards.  Tracking of individual devices is not likely.
10. Daughter Board panelization:

1. EMCal 2x4 daughter boards.  128 SiPMs per panel (2 panels/per full tray).
   
2. HCal panels need to be confirmed with vendor.   

More discussions are required.

Let me know if I missed anything.

Eric

-- 
Eric J. Mannel, Ph.D.
sPHENIX Group
Physics Dept.
Brookhaven National Laboratory
631/344-7626 (Office)
914/659-3235 (Cell)