Identification of light leptons and pions in the electromagnetic calorimeter of Belle II

The paper discusses new method for electron/pion and muon/pion separation in the Belle II detector at transverse momenta below 0.7 $\mathrm{G}\mathrm{e}\mathrm{V}\mathrm{/}c$, which is essential for efficient measurements of semi-leptonic decays of $B$ mesons with tau lepton in the final state. The method is based on the analysis of patterns in the electromagnetic calorimeter by using a Convolutional Neural Network (CNN).