Search for lepton-flavor violating decays of the Higgs boson in the μτ and eτ final states in proton-proton collisions at s =13 TeV

A search is presented for lepton-flavor violating decays of the Higgs boson to μ τ and e τ . The dataset corresponds to an integrated luminosity of 137 fb - 1 collected at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV. No significant excess has been found, and the results are interpreted in terms of upper limits on lepton-flavor violating branching fractions of the Higgs boson. The observed (expected) upper limits on the branching fractions are, respectively, B ( H → μ τ ) 0.15 ( 0.15 ) % and B ( H → e τ ) 0.22 ( 0.16 ) % at 95% confidence level.