Garra Ticó, JordiGraugés Pous, EugeniBABAR Collaboration2019-09-162019-09-162007-07-300031-9007https://hdl.handle.net/2445/140117We have performed a search for the flavor-changing neutral-current decays B → π ℓ + ℓ − , where ℓ + ℓ − is either e + e − or μ + μ − , using a sample of 230 × 10 6 Υ ( 4 S ) → B ¯¯¯ B decays collected with the BABAR detector. We observe no evidence of a signal and measure the upper limit on the isospin-averaged branching fraction to be B ( B → π ℓ + ℓ − ) < 9.1 × 10 − 8 at 90% confidence level. We also search for the lepton-flavor-violating decays B → π e ± μ ∓ and measure an upper limit on the isospin-averaged branching fraction of B ( B → π e ± μ ∓ ) < 9.2 × 10 − 8 at 90% confidence level.7 p.application/pdfeng(c) American Physical Society, 2007Física de partículesExperimentsParticle physicsExperimentsinfo:eu-repo/semantics/article5582042019-09-16info:eu-repo/semantics/openAccess