Determination of collision centrality using the MPD/NICA hadron calorimeter based on Bayes' theorem

Determination of collision centrality for heavy nuclei is necessary for any of the planned experiments at the MPD installation of the NICA collider at JINR. In a number of studies at high energies at the RHIC and LHC colliders, good results were obtained using the registration of spectators by forward hadron calorimeters. However, at intermediate energies at NICA of 2.5 – 5.5 GeV per nucleon, due to the insufficient intrinsic resolution for the released energy of the calorimeter, the problem should be studied in more details. In this work, based on Bayes' theorem, resolution estimates are obtained for the impact parameter (centrality), which differ from the results of direct modeling of the calorimeter with a fixed number of spectators.