Calibration of the photon spectrometer PHOS of the ALICE experiment
ALICE Collaboration (2019). Calibration of the photon spectrometer PHOS of the ALICE experiment. Journal of Instrumentation, 14, P05025. DOI: 10.1088/1748-0221/14/05/P05025
Published inJournal of Instrumentation
© 2019 CERN for the benefit of the ALICE collaboration.
The procedure for the energy calibration of the high granularity electromagnetic calorimeter PHOS of the ALICE experiment is presented. The methods used to perform the relative gain calibration, to evaluate the geometrical alignment and the corresponding correction of the absolute energy scale, to obtain the nonlinearity correction coefficients and finally, to calculate the time-dependent calibration corrections, are discussed and illustrated by the PHOS performance in proton-proton (pp) collisions at root s = 13 TeV. After applying all corrections, the achieved mass resolutions for pi(0) and eta mesons for p(T) > 1.7 GeV/c are sigma(pi 0)(m) = 4.56 +/- 0.03 MeV/c(2) and sigma(eta)(m) = 15.3 +/- 1.0 MeV/c(2), respectively.