sPHENIX tracking discussion

[Xudong Yu <yuxd AT stu.pku.edu.cn>]

Dear Hugo,

Thanks for your suggestion. Some additional information, and hope it would be useful. Before Run 51719, i made drift velocity calibration manually for most of the isobutane runs. After that, we are thinking about semi-calibration production pipeline. I think combining the semi-calibration workflow into official production is under consideration of production team, but not yet. Joe can make some comments if there is some updates on that.

Drift velocity calibration module using EMCal matching method in coresoftware: https://github.com/sPHENIX-Collaboration/coresoftware/tree/master/calibrations/tpc/TpcDVCalib

Corresponding macro in macro: https://github.com/sPHENIX-Collaboration/macros/tree/master/calibrations/tpc/TpcDVCalib

By using https://github.com/sPHENIX-Collaboration/macros/blob/master/calibrations/tpc/TpcDVCalib/drift.C, i make a plot to summarize available drift velocity for each runs. I would suggest to use the average values of drift velocity after run 51200, because you can see that there was a gas state change happening before run 51200. So, my suggestion is 0.00713 might be better before we have run-by-run calibration.

Best regards,

Xudong

Attachment: drift.pdf
Description: Adobe PDF document

On Oct 1, 2024, at 12:10, Pereira Da Costa, Hugo Denis Antonio (via sphenix-tracking-l Mailing List) <sphenix-tracking-l AT lists.bnl.gov> wrote:

All,
As discussed during today's tracking meeting,
The 'fallback' drift velocity that I have used to process run 53285
  G4TPC::tpc_drift_velocity_reco = 0.00726182; // from run 50015
whereas the default fallback value is 0.007 (from Common/Trkr_TpcReadoutInit.C)
I got this updated value from what's in the database, and using it, although not perfect, does improve the matching to the Silicons and to TPOT.

If people agree, I'd like to update the fallback value in the official macro.
This until we have an automatic way of getting the drift velocity on a per runnumber basis.

Hugo