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arXiv · 1906.08596

Global Bayesian Analysis of new physics in $b \to s \mu\mu$ transitions after Moriond-2019

Dinesh Kumar·Kamila Kowalska·Enrico Maria Sessolo
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Abstract

The recent measurement of $R_K$ at LHCb continues to support the hint of violation of lepton flavor universality. We perform a global fit for new physics in semileptonic $b\to s$ transitions using all the relevant data with a Bayesian analysis technique. We include new measurements of $R_K$ at LHCb and new determinations of $R_{K^*}$ and $R_{K^{*+}}$ at Belle. We perform the scan for various NP scenarios and infer the 68\% and 95.4\% credibility regions of the marginalized posterior probability density for all scenarios. We also compare the models in pairs by calculating the Bayes factor given a common data set. A few well-known BSM models are analyzed that can provide a high energy framework for the EFT analysis. These include the exchange of a heavy $Z^{'}$ boson in models with heavy vector-like fermions and a scalar field, and a model with scalar leptoquarks. We provide predictions for the BSM couplings and expected mass values.

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Dinesh Kumar, Kamila Kowalska, Enrico Maria Sessolo. 2019-06-20. Global Bayesian Analysis of new physics in $b \to s \mu\mu$ transitions after Moriond-2019. https://arxiv.org/abs/1906.08596

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