GlueX Start Counter Meeting, December 15, 2011
GlueX Start Counter Meeting
Thursday, December 15, 2011
10 am EST
JLab: CEBAF Center, Room L207
Contents
Agenda
- Announcements
- Review minutes from previous meeting
- Prototype Report
- SiPM configuration
- Contract Status
- Simulation Status
Communication Information
Video Conferencing
- ESNet: 8542554 (non-standard)
- EVO:
- Meeting URL: http://evo.caltech.edu/evoNext/koala.jnlp?meeting=e9eIeivevnaeaBIsaaI9
- Phone Bridge ID: 11 7685
Slides
Talks can be deposited in the directory /group/halld/www/halldweb1/html/talks/2011-4Q on the JLab CUE. This directory is accessible from the web at https://halldweb1.jlab.org/talks/2011-4Q/ . You have to be a member of the "halld" Unix group to put files in this directory.
Minutes
Present:
- FIU: Werner Boeglin, Puneet Khetarpal, Eric Pooser
- JLab: Chuck Hutton, Mark Ito (chair), Beni Zihlmann
Scintillator shaping and polishing
Werner was not happy with the scintillator shaped and polished and then re-polished by Plastic Craft. Two came back from re-polishing slightly better, two came back worse. He started looking for another vendor and has identified two candidates so far, [??? McNeal Enterprises] and [??? E&F Plastics]. He was send drawings to both, and both say that they can do the job. E&F proposes to mill all thirty counters out of a single solid piece of scintillator. (Plastic Craft presses the scintillator.) Responses from both companies have been prompt. The quotes come in at about $200 per piece. Subsequently, Werner send a "good" and "bad" scintillator to each; the "good" for re-re-polishing, the "bad" any destructive studies they care to do.
Re-measurement of Plastic Craft samples
Eric re-measured the two "good" scintillators after re-polishing by Plastic craft. He sees about 500 ps resolution from the far end and about 300 ps from the near end, a slight improvement from what was measured before re-polishing. These are unwrapped pieces, using SiPM read-out.
SiPM read-out
look at Werner's drawing
Beni: with no light guide, non-linearity when hits are near the end Eugene suggest modularity
need to do homework
