Influence of Misalignment on Track Reconstruction in the Time Projection Chamber of the MultiPurpose Detector (MPD)

Abstract

Using the previously developed alignment method for the Time Projection Chamber (TPC) in the MPD detector, the influence of misalignment on the reconstructed parameters of a charged particle track, such as transverse momentum and rapidity, is studied. The concept of a misalignment unit is introduced for the TPC. By simulating the TPC response to charged particles, distortions in the reconstructed track parameters depending on the magnitude of misalignment are analyzed. The influence of alignment errors on the reconstructed track parameters in the MPD TPC can be neglected. A systematic variation of the measured transverse momentum depending on the track projection width onto the readout plane is observed. This width is determined by the gas conditions and the electric field in the detector chamber. The alignment tools developed for the MPD Time Projection Chamber make it possible to estimate this width from experimental data and apply corrections to the reconstructed track parameters.