Electron/pion identification in the CBM TRD applying a ω n k goodness-of-fit criterion

Abstract

The problem of electron/pion identification in the CBM experiment based on the measurements of energy losses and transition radiation in the TRD detector is discussed. Earlier we analyzed a possibility to solve such a problem using an artificial neural network (ANN) [1]. Here we consider an approach based on a nonparametric ωnk goodness-of-fit criterion, and comparison with the ANN method is also performed. We show that both methods provide a comparable level of pion suppression and electron identification, the ωnk test is more simple for practical applications, the ANN method provides the needed level of pions suppression only if “clever” variables are used. We demonstrate that application of the ωnk-criterion to the J/Ψ reconstruction provides a high level of pion background suppression and significantly improves a signal-to-background ratio.