Commissioning and running of sPHENIX

[Jamie Nagle <jamie.nagle AT colorado.edu>]

Hello sPHENIXians,

This week marks the start of cryo-week #23 (out of 19 + 6 + 2 = 27).   The current pp data collection goes until 8 am on Monday, September 30, 2024 followed by 3 weeks of AuAu, i.e., until 8  am on Monday, October 21, 2024.     

There are just 12 days of pp data-taking remaining!

sPHENIX has continued to collect good quality physics data with the full detector complement.   With the new TPC FELIX firmware and some adjustments to buffer sizes, the streaming / extended readout for open heavy flavor is now maxing out around 30% with good stability and no substantial data dropping.     Last Friday's TPC Tracking/Performance Mini-Review was very encouraging that the tracking data is of good quality, while work remains to connect silicon hits to the TPC tracks.    Extra thanks to Joe Osborn and team for the very hard work and detailed presentation.    

On Friday, September 13, 2024, i.e., Friday the 13th, an issue developed with the MVTX cooling.     Through enormous effect by Cameron, Jimmy, and others, we only  lost about 1.5 stores worth of down time for Controlled Accesses and 1.5 stores of physics data taking but without the MVTX.      Note that one stave has been out during this mitigation.    The access today will hopefully bring the MVTX back to full operation.

For the jets & photons & upsilons with full tracking and |z| < 10 cm, sPHENIX to date has 19% of the original BUP goal of 45 pb^-1.     For the open heavy flavor from streaming readout, sPHENIX to date has 36% of the original BUP goal of 4.5 pb^-1.      The loss of data taking for resolving the MVTX cooling issues has been compensated for by the higher tracking streaming rate, and so sPHENIX is still on track to meet (and even exceed) the goal when we received the +2 week extension -- i.e., 50% of the BUP goal of 4.5 pb^-1 = 2.25 pb^-1.     However, since for the triggered data taking is simply luminosity and uptime limited, we might be slightly below our mark.   The graph below shows a summary of the run so far and the time remaining.    

Below are the links to the weekly RHIC Coordination meeting presentations from sPHENIX and C-AD.  

https://indico.bnl.gov/event/20768/contributions/96783/attachments/57325/98425/sPHENIXRunCoordinator_RHICCoordinationMeeting2024_09172024.pdf

https://indico.bnl.gov/event/20768/contributions/96782/attachments/57340/98446/RHIC_Coordination_Meeting_XXXIII-1.pdf

Lastly, welcome to our spectacular new sPHENIX shift crew (picture below) and the continuing Period Coordinator Martin Purschke (picture below).   

Sincerely,

Jamie

sPHENIX Run Coordinator 2024

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|| James L. Nagle   
|| Professor of Physics, University of Colorado Boulder

|| EMAIL:   jamie.nagle AT colorado.edu
|| SKYPE:  jamie-nagle        
|| WEB:      http://spot.colorado.edu/~naglej 
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