GlueX Start Counter Meeting, October 29, 2020

GlueX Start Counter Meeting
Thursday, October 29, 2020
10:00 am EDT
BlueJeans: 556 286 544

Agenda

1. Announcements
2. Review minutes from the last meeting
3. Dark Rate Studies
   • NIM Paper from QZB&S
4. Action Item Review

Minutes

Present: Rupesh Dotel, Mark Ito (chair), Simon Taylor, Beni Zihlmann

The main item of discussion was Beni's report on what he has gleaned thus far from the paper by Qiang, Zorn, Barbosa, and Smith on Radiation Hardness Tests of SiPMs for the JLab Hall D Barrel Calorimeter

• The authors conclude that SiPMs in the BCAL will last for the lifetime of GlueX.
• They do not address the situation for the start counter, so the question is if we can assess the neutron flux and/or radiation to the SiPM so much nearer the beam line.
• Beni has doubts about whether we can measure dark current in situ in the Hall.
• The asymptotic level of recovery from annealing is better at higher temperature.
• There is no history of annealing encoded in the SiPMs; an annealing session at low temperature does not adversely affect a later session at a higher temperature.

Action Item Review

1. Document calibration procedure (Rupesh)
2. Reproduce Beni's dark current results. (Tolga)
3. Continue to revisit Yi's study of SiPM annealing. (Mark, Beni)
4. Look up type of SiPMs used in start counter. (Mark)