Search for lepton-flavor-violating decays D0 →x0e±μ SEARCH for LEPTON-FLAVOR-VIOLATING DECAYS ⋯ LEES J. P. et al.

Abstract

We present a search for seven lepton-flavor-violating neutral charm meson decays of the type D0→X0e±μ, where X0 represents a π0, KS0, K̄∗0, ρ0, φ, ω, or η meson. The analysis is based on 468 fb-1 of e+e- annihilation data collected at or close to the (4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signals are observed, and we establish 90% confidence level upper limits on the branching fractions in the range (5.0-22.5)×10-7. The limits are between 1 and 2 orders of magnitude more stringent than previous measurements.