SoLID Ecal Weekly 20230406

Discussion on GEM

• Xinzhan's presentation
  • basic tracking is working now. Refer to SBS tracking: start from EC cluster, connect back to target, then select “grid” of each GEM layer. SoLID would also work this way. For beam test, we can’t do this because we do not want ECal to bias the samples
  • Showed some plots of offsets (p11), each seems to have 3 peaks (sharp, middle, wide). Not sure if the mean and sigma values of each plot represents real offsets, since we know the GEMs are aligned “by hand” to 5mm level while all sigma and offsets are very small, at 10um level. Xinzhan: these values should/could be fed back into tracking input as offsets.
• What about efficiency? – too early to tell.
• Suggestion: we should “branch out” the analysis now to PID of all other detectors and GEM tracking. For GEM tracking, should keep in mind that beam test data is a testing ground of SoLID tracking software.

Discussion on Runlist

• Mike organized runs into google slides
• still need to screen the MIP and SPE positions, as well as all other parameters of runs.
• Golden run(s):
  • Everyone will start from 4680 (TS1,3,4) 5uA run, with 1M events.
  • Note that Cherenkov HV optimized after run 4450 and we should all use runs after 4450 for analysis.

Summary of Analysis meeting Monday April 3rd

• GEM
  • Xinzhan: worked on making the GEM tracking software faster – now 40 times faster, from 4sec/100 events to <= 0.1 sec/100 events → 50k=50 sec or 1M events = 1000 sec.
  • Jimmy: it was 20-30 min/50k before shortening the code.
  • GEM number of clusters is nonlinear with beam current for GEM1/2, but GEM3/4 are very linear. Xinzhan said # of wires fired would be more useful to plot (not number of clusters).
  • Next: Jim will use the faster code for GEM optimization.
• Simulation -- Ye: was at DIS last week
• Cherenkov (Darren): code using GEM hit position is easy to do, will review/resume previous simulation PID study (used both electrons and pions)
• Runlist:
  • need MIP/SPE/threshold info, focus on 18 deg → Mike with Tim/Darren’s existing code+help
• PID:
  • Mike attempted getting photon analysis, but still looking at data.
• Next:
  • Mike will present a high-level data “buffet” (time in y * trigger in x * beam current as notes) for all 18 deg data
  • we can potentially divide up the data by trigger, study sim/data comparison and PID analysis, develop algorithm during month of April
  • Jump start all analysis (with GEM) in May.
• Hall update: Mike reported cables and many electronics are too hot to be released.