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

Research output: Contribution to journalArticle

Authors

  • LHCb Collaboration

Colleges, School and Institutes

External organisations

  • Nikhef National Institute for Subatomic Physics
  • Universität Zürich
  • Universidad de Santiago de Compostela
  • BRISTOL UNIVERSITY
  • University of Michigan, Ann Arbor.
  • LPC
  • University of Cincinnati
  • Laboratori Nazionali dell'Infn di Frascati
  • Technische Universität Dortmund
  • European Organization for Nuclear Research (CERN)
  • University of Glasgow
  • Universitat de Barcelona
  • Petersburg Nuclear Physics Institute (PNPI)
  • Imperial College London
  • Universidade Federal Do Rio de Janeiro (UFRJ)
  • IN2P3
  • Sezione INFN di Firenze
  • Laboratory of Photonics and Interfaces, Department de Chimie, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland. ahmad@mpip-mainz.mpg.de
  • Sezione INFN di Ferrara
  • University of Maryland, College Park, Maryland 20742 USA
  • CNRS/IN2P3
  • Institute for High Energy Physics (IHEP)
  • Syracuse University, Syracuse, New York 13244, USA
  • Yandex School of Data Analysis
  • INFN Sezione di Cagliari
  • Ruprecht-Karls-Universität Heidelberg
  • THE 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