Graugés Pous, EugeniBABAR Collaboration2019-04-042019-04-042007-02-081550-7998https://hdl.handle.net/2445/131457We report on a search for the lepton-flavor-violating processes e + e − → μ + τ − and e + e − → e + τ − . The data sample corresponds to an integrated luminosity of 211     fb − 1 recorded by the BABAR experiment at the SLAC PEP-II asymmetric-energy B Factory at a center-of-mass energy of √ s = 10.58     GeV . We find no evidence for a signal and set the 90% confidence level upper limits on the cross sections to be σ μ τ < 3.8     fb and σ e τ < 9.2     fb . The ratio of the cross sections with respect to the dimuon cross section are measured to be σ μ τ / σ μ μ < 3.4 × 10 − 6 and σ e τ / σ μ μ < 8.2 × 10 − 6 .8 p.application/pdfeng(c) American Physical Society, 2007Física de partículesExperimentsParticle physicsExperimentsinfo:eu-repo/semantics/article5582132019-04-04info:eu-repo/semantics/openAccess