UC Berkeley

Searches for the Higgs boson decays H → e e and H → e μ are performed using data corresponding to an integrated luminosity of 139 fb − 1 collected with the ATLAS detector in pp collisions at s = 13 TeV at the LHC. No significant signals are observed, in agreement with the Standard Model expectation. For a Higgs boson mass of 125 GeV, the observed (expected) upper limit at the 95% confidence level on the branching fraction B ( H → e e ) is 3.6 × 10 − 4 ( 3.5 × 10 − 4 ) and on B ( H → e μ ) is 6.2 × 10 − 5 ( 5.9 × 10 − 5 ). These results represent improvements by factors of about five and six on the previous best limits on B ( H → e e ) and B ( H → e μ ) respectively.