sPHENIX HCal discussion

[Anthony Michael Hodges <ahodges21 AT student.gsu.edu>]

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OptilcalFiberChecks(2).pdf

Hi everyone, 

Last week we had a meeting where the following slides were shared by Megan:

https://indico.bnl.gov/event/7802/contributions/35479/attachments/26886/40939/HCal_Meeting_March__3rd.pdf

Basically, they detail the appearance of two "peaks" (one around PR~0.8, and one around PR~1.0) in the distributions of the B23 and B26-type outer hadronic calorimeter tiles. Additionally, we also see a low PR tail form in the distributions for B27 and B28. As you can see from the presentation attached, the phenomenon appears both in Uniplast and GSU data. The following investigations are underway:

1) GSU has sent 8 B26 tiles, 4 from the PR~0.8 peak and 4 from the PR~1.0 peak, to Jamie Nagle's group at University Colorado Boulder to undergo a more thorough light yield test like that seen in the T-1044 test been paper. 

2) We here at GSU have used what equipment we have on hand to do a visual study of the differences between tiles, the results of which are attached. Unfortunately, they are mostly indeterminate. 

3) Uniplast, I believe, is also following up with its own investigation as to the source of this issue. I imagine Edward will let us know when they have a large update for us. 

I would expect more detailed updates at future HCal meetings, so stay tuned.

Cheers, 

-Anthony 

Anthony Hodges (he/him/his)

PhD. Candidate, Georgia State University

High Energy Nuclear Physics

ahodges21 AT student.gsu.edu