A new tagger for the charge identification of b-jets

A newly developed algorithm called the jet vertex charge tagger, aimed at identifying the sign of the charge of jets containing $b$-hadrons, referred to as $b$-jets, is presented in this note. In addition to the well established track-based jet charge determination, this algorithm introduces the so-called jet vertex charge reconstruction, which exploits the charge information associated to the displaced vertices within the jet. Furthermore, the charge of a soft muon contained in the jet is taken into account when available. All available information is combined into a multivariate discriminator produced using an artificial neural network method. The algorithm has been developed on jets matched to truth level $b$-hadrons provided by $t\bar{t}$ events simulated at $\sqrt{s}$ = 13 TeV using the full ATLAS detector simulation and reconstruction.