[PRad] [EXTERNAL] PAC51 slides

[Patrick Achenbach]

Dear all, 

I am not convinced by the statement on p. 30 that commercial Si detectors can be operated at 20 K. At temperatures below 100 K, charge carriers freeze out (in pure silicon this happens at T ~ 40 K). Many SiPMs fail to operate at cryogenic temperatures or show deteriorating changes in their pulse shapes. Also the afterpulse probability in SiPMs has been seen to increase dramatically caused by ion traps. The referenced Conference Proceedings show a study with a Hamamatsu VUV MPPC which was designed to work below liquid nitrogen temperatures, but other types from Hamamatsu failed due to large changes in resistance. In my opinion, one needs to validate the properties of the proposed Si detectors at 20 K.

Patrick


________________________________________
From: PRad <prad-bounces at jlab.org> on behalf of Dipangkar Dutta via PRad <prad at jlab.org>
Sent: Thursday, June 29, 2023 19:28
To: prad
Subject: [PRad] [EXTERNAL] PAC51 slides

Hi All,
Here are the draft PAC51 slides for DRad. Please take a look and we
can discuss it during the meeting tomorrow.
Cheers
Dipangkar