GlueX Start Counter Meeting, November 17, 2011
GlueX Start Counter Meeting
Thursday, November 17, 2011
10 am EST
JLab: CEBAF Center, Room F326/7
Contents
Agenda
- Announcements
- Review minutes from previous meeting
- Prototype Report
- SiPM configuration
- Contract Status
- Simulation Status [1]
Communication Information
Video Conferencing
- ESNet: 8542553
- EVO:
- Meeting URL: http://evo.caltech.edu/evoNext/koala.jnlp?meeting=292I2iMeMB9M9nDD9aD9
- Phone Bridge ID: 10 1295
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: Lei Guo, Puneet Khetarpal
- JLab: Eugene Chudakov, Chuck Hutton, Mark Ito (chair), Tim Whitlatch
Prototype Report
Lei reports that they got the scintillators back from Plastic Craft after re-polishing. Three of them came back badly crazed. One was OK. He says they made two mistakes:
- They ignored the recommendation to only use isopropyl alcohol to clean the surfaces. Instead they used a solution of isopropyl alcohol and naphtha. The naphtha is petroleum based and attacked the scintillator surface.
- They processed the counters in the following order: bend, machine, then polish. Preferred is: machine, polish, then bend.
Plastic Craft has agreed to replace the scintillator and will try again with the new pieces. They will place an order with Eljen.
FIU will test the undamaged piece. Its surface quality seems to have improved after re-polishing.
werner looked at it, some candidates
1x4 or 1x5 favored
with 30 paddles
look at different products from H; mantis!!!
2x4 would also work
actively explore using 4x4 as is
explore opening up diameter of sc array
look in catalog
werner back next week
simple light guide design better
overlap between rohacell
need to make target geometry consistent
need a tagged release
action item, update drawings
are flat sides polished? usually come smooth from manufacturer
one concern: puneet, straight portion,
this simulation 24 paddles
working on rate and radiation dose using geant4