1) Centrality determination for Run14 prod_high - Xiaolong Chen
a. Latest work on centrality calibration for Run14 high luminosity production, as the previous calibration parameters extracted using low/mid luminosity data are not suitable for high luminosity data. See slide 2
b. Slide 4
i) the h values for Vz > 50 cm or so are above the red line in the right figure, while the fit to this region seems quite good as shown in the left figure. Furthermore, the error bars on these data points are larger after correction. Need to check.
ii) the fit to the region around Vz = -50 cm does not seem to work well. Suggest to try even higher-order polynomial functions to improve the situation.
iii) the gRefMult values are higher at large |Vz| values, which seems to be related to the detector effect as this behavior also shows up in 2016
c. Slide 11: these new calibration parameters should only apply to events with ZDCx > 55 kHz, as the h value for ZDCx < 55 kHz drops down quickly. Also most of the high luminosity data have ZDCx > 55 kHz.