Geometric calibration of the SND detector electromagnetic calorimeter

This paper presents the design, implementation and validation of the software alignment procedure used to perform geometric calibration of the electromagnetic calorimeter with respect to the tracking system of the SND detector which is taking data at the VEPP-2000 e+e− collider (BINP, Novosibirsk). This procedure is based on the mathematical model describing the relative calorimeter position. The parameter values are determined by minimizing a χ2 function using the difference between particle directions reconstructed in these two subdetectors for e+e−→e+e− scattering events. The results of the calibration applied to data and MC simulation fit the model well and give an improvement in particle reconstruction. They are used in data reconstruction and MC simulation.