Star-tpc-l mailing list

[Richard Witt <witt AT usna.edu>]

Present: Alexei, Jim, Yuri, Tommy, Frank, Mathias, Sonoraj, Flemming, and myself

== Hardware

— everything is working well

— checked TPC vs magnet position again for Yuri

— sensors were installed this past February

— no motion detected, even with polarity flip

— overall TPC is shifted by small amount (~1 mrad), but this took place before sensor installation

== Electronics

— analyzed all runs for past two weeks

— iTPC dead channels vary from 12 to 15 on a regular basis

— TPX has 7 RDOs down

— may be permanent through next year

— TPX is about 15% dead (7 out of 48 RDOs) at present

== Software

— Run 22 p+p 500 SC

— subset of fills (few hundred jobs) with one more pass

— SC calibration is _done_ with old TPC alignment once that pass is done

— will then proceed with more passes once new alignment is available

— T0 study 

— look at all data from 2019 - 2021

— 9.2 GeV (days 178 - 180 and day 195-196) shows 100 ns timing split vertex

— 9.8 GeV shows approximately 1 time bucket splitting

— d+Au (2021, days 180-183) also shows approximately 1 time bin splitting

— see: https://drupal.star.bnl.gov/STAR/blog/fisyak/STAR-Trigger-delays-Run-XIX-XXI

— TFG24d

— some fixes implemented including those accounting for old alignment scheme

— jobs have been resubmitted to test fixes

— in 2 weeks, Yuri will be gone for 2 weeks

— QA plots from Mathias show slightly smaller reduced Chi^2 (1.83 vs. 1.95)

— secondary and tertiary peaks in vertex distribution observed in P24ia are gone in TFG24d

— discontinuity in DCA Y is still there (TFG24c vs TFG24d)

— reduction in Chi^2 is thought to be too small

== AOB

— Readiness of alignment changes for FXT production?

— many comments in PR

— library has been built by Gene with new alignment

— for FXT, Yuri would like to use that library to produce calibration sample

— new alignment needs new options

— test was done to ensure new options are compatible with older libraries (was successful)

— status summary will be sent to TPC list

— no follow-up yet on the 0.1 Hz ripple on power lines

— weekly reservation still needs to be updated in Drupal (some difficulty getting meeting added, R. Witt will follow-up)

Best Regards,

  Richard

Sent from my iPad

-- 
"Education is the most powerful weapon which you can use to change
the world."

--Nelson Mandela

~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~
 Richard Witt, Professor of Physics     Phone (USNA): 410-293-6675
    United States Naval Academy         Email: witt AT usna.edu
~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~~~***~