Reconstruction and selection of J/ψ → e+e− decays registered by CBM setup in 25 AGeV AuAu collisions

The problem of reconstructing and selecting J/ϕ → e + e − decays registered by the CBM setup in AuAu collisions at 25 AGeV beam energy is considered. The key task in this problem is fast and reliable electron-positron identification using the energy losses of charged particles in the Transition Radiation Detector (TRD). We consider two methods for solving this problem: an artificial neuron network (ANN) and a modified non-parametric goodness-of-fit ω n k criterion. Our analysis shows that both approaches give similar results for the J/ϕ → e + e − yield and the signal-to-background ratio. Compared with the ω n k criterion, the method based on ANN has a number of disadvantages which are discussed in detail. Taking into consideration the very simple software implementation of the ω n k algorithm, it can be used for J/ϕ → e + e − decays selection in a real-time experiment.