Difference between revisions of "GlueX TOF Meeting, December 20, 2012"
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==Scintillator Bars== | ==Scintillator Bars== | ||
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| − | + | The six scintillator bars for the mini-TOF have been received at FSU: 2 regular, 2 half-width, and 2 half-length bars. Eljen's [http://hadron.physics.fsu.edu/TOF/doc/Eljen_Dimension_Report-1stArticle.pdf measurements of the dimensions] show that some are out of tolerance by one or two mils less than the 5 mil limit. Eljen also shipped [http://hadron.physics.fsu.edu/TOF/doc/Eljen_Scint_Test_Report-1stArticle.pdf performance data] on the scintillator. (The interpretation of the "light output" spectrum a mystery currently.) | |
| − | + | Although they have not been shipped yet, Eljen reports that in the next batch of 76 regular bars, 12 of them are 1/8 inch short. A decision on whether to accept these has not been made. Chuck will look at the mechanical implications. | |
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| − | 1/8 | + | |
| − | not | + | |
| − | + | Sasha is setting up for measurements on the scintillator received. They will be put into the dark box, with a spring loaded mechanism to hold the PMTs, and tested with a strontium source at various locations along the bar. Both ADC and TDC data will be taken to get attenuation length and speed of light. | |
| − | put into dark box | + | |
| − | spring loaded mechanism to hold | + | |
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| − | get | + | |
| − | light | + | |
==Mini-TOF Assembly== | ==Mini-TOF Assembly== | ||
Revision as of 12:43, 20 December 2012
GlueX TOF Meeting
Thursday, December 20, 2012
10:00 am EDT
JLab: CEBAF Center, F326
Contents
Agenda
- Announcements
- Review of last TOF bi-weekly meeting
- Mechanical design
- MiniTOF
- TOF Gluing Fixture
- TOF Module Wrapper
- PMT testing
- Contract status
- Calibration and Alignment
- Technical Design Report contribution
Communication
Videoconference
- ESNet: 8542553
- EVO: EVO site
- meeting link
- Phone bridge ID: 15 1627
Slides
Talks can be deposited in the directory /group/halld/www/halldweb1/html/talks/2012-4Q on the JLab CUE. This directory is accessible from the web at https://halldweb1.jlab.org/talks/2012-4Q/ .
Minutes
Present: FSU: Sasha Ostrovidov JLab: Chuck Hutton, Mark Ito (chair)
PMT Testing
- There are four undergraduates working on testing PMTs now.
- 130 PMTs have been received (batches 1, 2, and 3).
- All of them have been tested with an LED, with gain measured via a visible single-photoelectron peak. All tubes passed.
- 70% of them have been tested with an americium source to look at photocathode efficiency
- 10% of them have been tested with a cesium source on a sodium iodide crystal.
Wrapping Material
Paul Eugenio has succeeded in negotiating purchase of rolls of ESR material from 3M, rather than in the 2×3 foot sheets that were originally offered. The rolls are 8 inches wide and about 1000 feet long. Also, there will be no adhesive layer attached to the material; the total thickness will be 1 mil. The purchase order has already been sent to 3M. Shipment is expected sometime in January.
Scintillator Bars
The six scintillator bars for the mini-TOF have been received at FSU: 2 regular, 2 half-width, and 2 half-length bars. Eljen's measurements of the dimensions show that some are out of tolerance by one or two mils less than the 5 mil limit. Eljen also shipped performance data on the scintillator. (The interpretation of the "light output" spectrum a mystery currently.)
Although they have not been shipped yet, Eljen reports that in the next batch of 76 regular bars, 12 of them are 1/8 inch short. A decision on whether to accept these has not been made. Chuck will look at the mechanical implications.
Sasha is setting up for measurements on the scintillator received. They will be put into the dark box, with a spring loaded mechanism to hold the PMTs, and tested with a strontium source at various locations along the bar. Both ADC and TDC data will be taken to get attenuation length and speed of light.
Mini-TOF Assembly
all parts made for mini-tof mid january start gluing, finish tresting this week start early january gluing ESR
Design Work
chuck is putiing mini tof ideas into final design
Chuck thinks eyes-on would be a good idea.
