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A challenge to lepton universality in B meson decays

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Abstract

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.

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Authors and Affiliations

  1. SLAC National Accelerator Laboratory, Stanford, CA, 94309, USA

    Vera Lüth

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  1. Vera Lüth
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Correspondence to Vera Lüth.

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This article is part of the Topical Collection on Proceedings of the 7th Symposium on Symmetries in Subatomic Physics (SSP 2018), Aachen, Germany, 10-15 June 2018

Edited by Hans Ströher, Jörg Pretz, Livia Ludhova and Achim Stahl

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Lüth, V. A challenge to lepton universality in B meson decays. Hyperfine Interact 239, 59 (2018). https://doi.org/10.1007/s10751-018-1531-1

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