Search for the lepton-flavor-violating $\tau^- \to e^{\mp}\ell^{\pm}\ell^-$ decays at Belle IIAdachi, Ichiro (Avtor) Borah, Jyotirmoi (Avtor) Bračko, Marko (Avtor) Korpar, Samo (Avtor) Križan, Peter (Avtor) Pestotnik, Rok (Avtor) Podobnik, Tomaž (Avtor) Šantelj, Luka (Avtor) Starič, Marko (Avtor) experimental physicsflavour physicsphysics of elementary particlesWe present the result of a search for the charged-lepton-flavor violating decays $\tau^- \to e^{\mp}\ell^{\pm}\ell^-$, where $\ell$ is a muon or an electron, using a data sample with an integrated luminosity of 428 fb$^{-1}$ recorded by the Belle II experiment at the SuperKEKB $e^+e^-$ collider. The selection of $e^+e^- \to \tau^+\tau^-$ events containing a signal candidate is based on an inclusive-tagging reconstruction and on a boosted decision tree to suppress background. Upper limits on the branching fractions between 1.3 and 2.5 × 10$^{-8}$ are set at the 90 % confidence level. These results are the most stringent bounds to date for four of the modes.20252026-01-30 13:18:35Članek v reviji178842sl