Search for the baryon- and lepton-number violating decays B⁰ → pμ⁻ and B⁰_s → pμ⁻

A search for the baryon- and lepton-number violating decays B⁰ → pμ⁻ and B⁰_s → pμ⁻ is performed at the LHCb experiment using data collected in proton-proton collisions at √s=7, 8 and 13 TeV, corresponding to integrated luminosities of 1, 2, and 6  fb⁻¹, respectively. No significant signal for B⁰ → pμ⁻ and B⁰_s → pμ⁻ decays is found and the upper limits on the branching fractions are determined to be B(B⁰ → pμ⁻) < 2.6(3.1)×10⁻⁹ and B(B⁰_s → pμ⁻) < 12.1(14.0)×10⁻⁹, respectively, at 90% (95%) confidence level. These are the first limits on these decays to date.