Difference between revisions of "May 2, 2013 SiPM Electrical and Cooling"

Latest revision as of 12:41, 3 May 2013

Action Items from previous meetings

1. Interface with Tom for optimum placement of tubing in cooling plate during gluing. Provide a cover plate to assist with alignment. (Chris and Nic)
2. Mount one of the completed assemblies onto a module in the ESB to evaluate any possible interferences with cables. (Chris and Nic)\
3. Check on status of returning "borrowed" SiPM (Elton)

Tentative Agenda

1. Announcements
2. Action Items
3. Light guides (Tina)
4. SiPM production testing (Yi)
5. Mechanical assembly (Jim)
6. Electronic boards and SiPM sorting (Fernando and Chris)

Minutes

Attending: Chris, Tina, Elton, Jim, Nic

1. Announcements
2. Action Items
   • Length of tubing can be accommodated with RTV on the joint
   • New assemblies have the cables tucked in so should be ok to mount, but should still check.
3. Light guides (Tina)
   • Four modules are on the floor in the hall so that they can be monitored
   • Two modules were partially repaired after gluing with old procedure. Some of these seem to have more issues than originally thought. The problems may not have been missed during original inspection. But careful monitoring will continue from now on.
   • Two modules have been glued with the new procedure
   • Elton: Sent a summary of the new procedure to Tim Norland for comments. He did not have any concerns. We also clarified that the glue needs 3.5 J/cm2 (not 2.5 J/cm2 as in part of the literature) for full curing
   • With the new procedures the base should be receiving > 6 J/cm2
   • The new procedures seem to work well. Gluing goes smoothly and no problems have developed.
   • Black spots on modules in the hall, caused by uncured glue wetting the surface of the Tedlar to the light guide, have been wiped and mostly removed. However, if the glue is not completely removed, the spots come back. We need to clear these before beginning a regimen of full illumination on the previous modules.
4. Light guide testing (Elton)
   • New fixtures and procedures for testing have been implemented successfully. Transmission tests were presented at the Bcal Readout meeting.
   • Some discussion regarding how to proceed with modules glued with old procedure. Would like to clean "black spots". Guides that are not planned for replacement should be illuminated 50 s to ensure complete curing. One may wish to replace other guides before a systematic program for new illumination.
5. SiPM production testing (Yi)
6. Mechanical assembly (Jim)
   • Two fixtures have arrived
   • One fixture to position the light source. The fixture has adjusted after curing one column
   • Tina has checked the new fixtures and seem to work well.
   • The second fixture is a tool to replace single light guides
7. Electronic boards and SiPM sorting (Fernando and Chris)
   • 20 fully tested assemblies.
   • Procedures are being refined and both Chris and Nic are now able to assemble a full module with no rework!
8. Other
   • Students from collaborating institutions will be at JLab for the summer. We need to find appropriate projects for them that fits their timeline. The list of students and schedules can be found at Summer 2013 Manpower Contributions
   • BCAL Video of students fabricating the lead scintillator matrix