GlueX Start Counter Meeting, July 28, 2011
Contents
Location, Time
Thursday, July 28, 2011
3:30 pm EDT
JLab: CEBAF Center, Room F326/7
Agenda
- Announcements
- Review minutes from previous meeting: all
- Start Counter News
- MOU status
Communication Information
Telephone
To connect by telephone:
- dial:
- US and Canada: (866)740-1260 (toll free)
- International: (303)248-0285 (toll call) or look up toll-free number at http://www.readytalk.com/intl
- enter access code followed by the # sign: 3421244#
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/2011-3Q on the JLab CUE. This directory is accessible from the web at https://halldweb1.jlab.org/talks/2011-3Q/ . You have to be a member of the "halld" Unix group to do this.
Minutes
Present:
- FIU: Werner Boeglin, Lei Guo, Eric Pooser
- JLab: Eugene Chudakov, Mark Ito (chair), Puneet Khetarpal, Sascha Somov, Simon Taylor, Tim Whitlatch, Beni Zihlmann
box in operation
using to test long solid light guide
at end of 140, lose factor of 2 in time resolution
6mm thich by 10 mm wide
10 mm wide scintillator
tried using without wrapping
and with reflective material,
used grease -> 1.5
got scintillator from plastic craft look at them recently quality not that great, scratches, milky scintillato that looks worse at tend of scintillator, 300-400 ps bend section, just about as good go to small point , 600 ps fmpmt connect to light guide, 600 ps- 1 ns expected can be improved by scint surface quality want to measure all 5 to see if response if uniform vapor polishing look promising
today, tried fiber light guide, new mounting will be connecting to try now working only with photomultipliers intrinsically better resolution
fmpmt, max field one tesla, orientation crucial, at 30 degrees, optimal
tim want drawing, straight 394 mm straight, bend readius 20 mm, 17 degrees
werner will send drawing to tim
werner thinks cylindrical, eugene raised lots of fiber if you come up with idea on bend section then werner will try might lose a lot of light
sipm fernando, managed to get sub ns resolution, bias voltage not stable, added capacitor close to sipm, bypass cap, rise time went to 5 ns, decay issues
sasha 180 ps for 3mm sipm 20-22 ns 16 ns
MOU going around for signatures
