Search for the lepton flavour violating decay $B^+ \rightarrow K^+ μ^- τ^+$ using $B_{s2}^{*0}$ decays
hep-ex
/ Authors
LHCb collaboration, R. Aaij, C. Abellán Beteta, T. Ackernley, B. Adeva, M. Adinolfi, H. Afsharnia, C. A. Aidala, S. Aiola, Z. Ajaltouni
and 900 more authors
S. Akar, P. Albicocco, J. Albrecht, F. Alessio, M. Alexander, A. Alfonso Albero, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves, S. Amato, Y. Amhis, L. An, L. Anderlini, G. Andreassi, M. Andreotti, F. Archilli, A. Artamonov, M. Artuso, K. Arzymatov, E. Aslanides, M. Atzeni, B. Audurier, S. Bachmann, J. J. Back
/ Abstract
A search is presented for the lepton flavour violating decay $B^+ \rightarrow K^+ μ^- τ^+$ using a sample of proton--proton collisions at centre-of-mass energies of 7, 8, and 13 TeV, collected with the LHCb detector and corresponding to a total integrated luminosity of 9 fb${}^{-1}$. The $τ$ leptons are selected inclusively, primarily via decays with a single charged particle. The four-momentum of the $τ$ lepton is determined by using $B^+$ mesons from $B_{s2}^{*0} \rightarrow B^+ K^-$ decays. No significant excess is observed, and an upper limit is set on the branching fraction $B(B^+ \rightarrow K^+ μ^- τ^+) < 3.9 \times 10^{-5}$ at 90% confidence level. The obtained limit is comparable to the world-best limit.