Hyperfine Interactions

, 239:59 | Cite as

A challenge to lepton universality in B meson decays

  • Vera LüthEmail author
Part of the following topical collections:
  1. Proceedings of the 7th Symposium on Symmetries in Subatomic Physics (SSP 2018), Aachen, Germany, 10-15 June 2018


One of the key assumptions of the Standard Model of fundamental particles is that the interactions of the charged leptons, namely electrons, muons, and taus, differ only because of their different masses. While precision tests have not revealed any definite violation of this assumption, recent studies of B meson decays involving the higher-mass tau lepton have resulted in observations that challenge lepton universality at the level of four standard deviations. A confirmation of these results would point to new particles or interactions, and could have profound implications for our understanding of particle physics.


Lepton universality Flavor physics BABAR Belle LHCb 


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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.SLAC National Accelerator LaboratoryStanfordUSA

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