Search for lepton-universality violation in B+→K++decays

Research output: Contribution to journalArticlepeer-review

Authors

  • LHCb Collaboration

Colleges, School and Institutes

External organisations

  • Nikhef National Institute for Subatomic Physics
  • University of Zurich
  • Universidad de Santiago de Compostela
  • University of Bristol
  • University of Michigan
  • LPC
  • University of Cincinnati
  • Laboratori Nazionali dell'Infn di Frascati
  • TU Dortmund University, Germany
  • CERN
  • University of Glasgow
  • Universitat de Barcelona
  • Petersburg Nuclear Physics Institute (PNPI)
  • Imperial College London
  • Universidade Federal Do Rio de Janeiro
  • IN2P3
  • Sezione INFN di Firenze
  • Ecole Polytechnique Federale de Lausanne
  • Sezione INFN di Ferrara
  • University of Maryland
  • Institute for High Energy Physics (IHEP)
  • Syracuse University
  • Yandex School of Data Analysis
  • INFN Sezione di Cagliari
  • Ruprecht-Karls-Universität Heidelberg
  • University of Warwick
  • Laboratoire Leprince-Ringuet
  • Institute of Physics
  • Max-Planck-Institut für Kernphysik (MPIK)

Abstract

A measurement of the ratio of branching fractions of the decays B+→K+μ+μ- and B+→K+e+e- is presented. The proton-proton collision data used correspond to an integrated luminosity of 5.0  fb-1 recorded with the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. For the dilepton mass-squared range 1.1<q2<6.0  GeV2/c4 the ratio of branching fractions is measured to be RK=0.846-0.054+0.060-0.014+0.016, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of RK to date and is compatible with the standard model at the level of 2.5 standard deviations.

Details

Original languageEnglish
Article number191801
Number of pages13
JournalPhysical Review Letters
Volume122
Issue number19
Early online date13 May 2019
Publication statusPublished - 17 May 2019

ASJC Scopus subject areas