Difference between revisions of "GlueX TOF Meeting, December 12, 2011"
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==Attaching the PMT's== | ==Attaching the PMT's== | ||
| − | + | We discussed various ways of attaching the PMT's to the light guides in light of the need to replace tubes in the future if rates are what we expect. | |
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| − | + | * '''optical glue (epoxy?)''': Paul is using this now. He reports success separating the PMT's from the light guides and re-establishing good optical contact. | |
| + | * '''optical grease''': Easy to detach the tube, harder to support mechanically | ||
| + | * '''optical cookie''': ditto | ||
| + | * '''RTV''': Eugene reported a good experience using this with lead glass blocks and PMT's. Strong glue joint and easy damage-free un-gluing. | ||
| − | + | Clearly, we need to study the various options. Eugene will send Paul information on the RTV so that he can try that. | |
| − | Eugene will send | + | |
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got copy of new light guide | got copy of new light guide | ||
Revision as of 17:00, 12 December 2011
Monday, December 12, 2011
9:30 am EST
JLab: CEBAF Center, Room F326
Contents
Agenda
- Announcements
- Minutes from the last meeting
- Mechanical design: Tim, Chuck
- Prototype status: Paul, Sasha, Beni, Test Stand at FSU
- Trip Report
- Splitter or dynode for ADC?
- Prototype studies [1]
- Contract Status: Mark
- Construction Manual
- Quality Assurance Plan/Acceptance Procedures
- Construction Manager
- Construction Schedule
Communication
Videoconference
- ESNet: 8542553
- EVO: EVO site
- direct meeting link
- Phone Bridge ID: 443 0818
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/ .
Minutes
Present:
- FSU: Paul Eugenio, Sasha Ostrovidov
- JLab: Eugene Chudakov, Chuck Hutton, Mark Ito (chair), Simon Taylor, Beni Zihlmann
Trip Report: Work at FSU
Beni reported on work he, Sasha, and Paul did during Beni's recent trip to FSU (November 28 through December 2). He led us through his wiki page summarizing the work. He described:
- cosmic ray test stand at FSU
- PMT gain measurements
- revised PMT current estimates
- time difference resolution measurements
Most encouraging, he gets a Δt/2 resolution of 80 ps near the center of the TOF prototype.
We agreed that the trip was very useful and will help with communication in the future.
Prototype Tests
Sasha showed progress in the last week with the prototype. See his [??? web page] for details. He showed:
- improvement in trigger counter time difference measurements after Paul changed the phototubes
- improved separation between pedestal and signal in the TOF prototype paddle with a longer ADC gate
PMT Choice
We discussed the various option for the PMT purchase. Beni agreed to summarize the arguments and proposals and send them out to the list.
Attaching the PMT's
We discussed various ways of attaching the PMT's to the light guides in light of the need to replace tubes in the future if rates are what we expect.
- optical glue (epoxy?): Paul is using this now. He reports success separating the PMT's from the light guides and re-establishing good optical contact.
- optical grease: Easy to detach the tube, harder to support mechanically
- optical cookie: ditto
- RTV: Eugene reported a good experience using this with lead glass blocks and PMT's. Strong glue joint and easy damage-free un-gluing.
Clearly, we need to study the various options. Eugene will send Paul information on the RTV so that he can try that.
got copy of new light guide
paul vinyl cutter for vm2000 paul will work on getting bigger sheets or a roll
