Calibration readiness overview

Speaker : Gene V. Buren ( BNL )


Talk time : 12:15, Duration : 00:15
RUN 13 pp510:

Reminder: calibrating data from before PXL insertion (i.e. days 74-128); we need to account for PXL geometry in reconstruction for days 129-161.
  • TOF:
    • Calibration production: processed using You do not have access to view this node, as discussed at last S&C meeting.
    • BTOF:
      • Timing: the plan is to reuse the BTOF calibration of Run-12's U+U (stop side timing calibrations have been rather stable in the past, and calibrating it with p+p is difficult).
      • Alignment: since parts a TOF calibration rely on the accuracy with which we can extrapolate to the modules it is important to make sure that the relative alignment between TPC and TOF is accounted for.
        • For each TPC calibration we know that this changes (especially along the phi direction).
        • A first check on the alignment shows that the relative (phi) alignment of the east and west sectors changed by a few mm (at the TOF). The change is perhaps not very relevant in terms of the local-Z calibration, but may have an impact on the overall matching efficiency if not adjusted.
        • In addition, we seem to have matching problems to the GEMTOF trays (i.e. trays with GMT modules) ... it's not clear at this moment whether that is a result of a significant alignment change (these trays have been moved in and out), a timing issue (recall that the first TDIG had to be removed in order to install the GEM), or a software/mapping issue. On the other hand, this particular issue only affects 4 trays which we ultimately could disable in the calibration.
    • VPD:
      • The calibration is in principle ready to be rolled out and all that is needed is to account for a shift in the global timing offset between BTOF and VPD. This offset is the result of a combination of changes in the VPD high-voltage settings (adjusted for each run), and changes in the delay because of minor changes in the cabling (we've found timing to be sensitive to changes in the way the cables are redressed).
    • Estimated completion: 1-2 weeks (some unexpected delays from realigning workforce, but moving forward)
  • TPC:
    • dE/dx:
      • Completed (see Yuri's presentation).
      • Requires new codes (i.e. new production library)
      • Runs 14126017 - 14128018 are missing TPC anode voltages (could be recovered by data analysis, but this is a signficant amount of work. Data would only be useful for analyses which do not require PID (W boson?). Exclude for now.
    • hit errors:
      • In progress (should only take a few days)
    • distortion codes:
      • Account for ~10-20% of the reconstruction time in pp510.
      • Speeding up by a factor of ~4 has been found and is in testing (should only take a few days).
Run 12 CuAu:
  • TPC:
    • SpaceCharge:
      • Asymmetric system (only other one so far was dAu), eventually needs some careful attention.
      • First attempt completed: ~4% asymmetry (was ~20% for dAu), will be uploaded to DB by the end of the week.