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arXiv · 2110.13270

$B$ Flavour Anomalies: 2021 Theoretical Status Report

David London·Joaquim Matias
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Abstract

At the present time, there are discrepancies with the predictions of the SM in several observables involving $b \to s \ell^+ \ell^-$ and $b \to c \ell^- {\bar\nu}_\ell$ decays. These are the $B$ flavour anomalies. In this review, we summarize the data as of Moriond 2021 and present theoretical new-physics explanations from both a model-independent effective-field-theory point of view and through the building of explicit models. Throughout, we stress the complementarity of these two approaches. We also discuss combined explanations of both $B$ anomalies, and present models that also explain other problems, such as dark matter, $(g-2)_\mu$, neutrino properties, and hadronic anomalies.

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David London, Joaquim Matias. 2021-10-25. $B$ Flavour Anomalies: 2021 Theoretical Status Report. https://doi.org/10.1146/annurev-nucl-102020-090209

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