A Challenge to Lepton Universality in B Meson Decays

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.

Invited tall at 7th Symposium on Symmetries in Subatomic Physics (SSP 2018) at RWTH Aachen University (Germany), June 11-15, 2018

References in corpus (15)

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Cited by in corpus (4)

• Renormalization-group evolution of new physics contributions to (semi)leptonic meson decays
• Direct CP violation in beauty and charm hadron decays
• CP asymmetry in $\tau \to K_S\pi {\nu }_{\tau }$ decays within the Standard Model and beyond
• Diffractive Dissociation of Alpha Particles as a Test of Isophobic Short-Range Correlations inside Nuclei