sPHENIX MAPS tracker discussion

[Hao-Ren Jheng <hrjheng AT mit.edu>]

Dear all,

I have updated the chip occupancy comparison, attached below, to include the distribution from Run 45936 with a -2 mrad crossing angle Run 49035 with a +1.5 mrad*.

Key findings are: (1) We observed a similar level of chip occupancy in -2 mrad, and (2) a significantly lower level of chip occupancy in +1.5 mrad. 

As discussed in today's shift change meeting, we need to address the following question:

Given that we have already turned on MVTX during the -2 mrad beam crossing to collect data with comparable chip occupancy levels, is it OK to leave MVTX ON during STAR steering?

I propose we discuss this matter in this email thread. We can then present our final decision at tomorrow's shift change meeting and update the standing order and detector summary accordingly.

Best,

Hao-Ren

* Jamie’s email on July 22 “[[Sphenix-run-l] ] special run configurations (start of 0 crossing physics data, B=0 runs, test with +1.5 mrad crossing)"

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