Run 15 pp200

Preliminary calibration (no tilt, from HFT):
  • Xin Dong determined the position of the beam spot at z=0 with respect to the center of the PXL (see the "all triggers" result of this page: Run15 pp 200 GeV beam position check)
  • Transforming this to global coordinates results in (x0,y0) = (0.01,-0.24)

Run 15 pp200 preliminary 2

Final calibration?

Run 15 pp200 preliminary 2

The first preliminary calibration, using HFT only, found (x0,y0) = (0.01, -0.24), using a production of data from run 16048027. The HFT cannot, however, determine a beam tilt. Using the same data, with TPC-found primary vertices, I find similar (x0,y0) = (0.002 ± 0.003, -0.259 ± 0.003), which is only different by ~1/5th of a mm. I find slopes of dx/dz = -0.00040 ± 0.00007, and dy/dz = 0.00045 ± 0.00007. As I did for the pAu preliminary calibration, I will use the HFT-found intercepts, and the TPC-found slopes.


-Gene