0000000000194933

AUTHOR

S. Neshatpour

Present Status of b → sℓ + ℓ − Anomalies

Abstract We discuss the observed deviations in b → s l + l − processes from the Standard Model predictions and present global fits for the New Physics description of these anomalies. We further investigate the stability of the global fits under different theoretical assumptions and suggest strategies and a number of observables to clear up the source of the anomalies.

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New global fits to $b \to s$ data with all relevant parameters

The LHCb experiment has made several measurements in $b \to s$ transitions which indicate tensions with the Standard Model predictions. Assuming the source of these tensions to be new physics, we present new global fits to all Wilson coefficients which can effectively receive beyond the Standard Model contributions. While the theoretically clean ratios $R_{K^{(*)}}$ which are sensitive to lepton flavour non-universality may unambiguously establish lepton non-universal new physics in the near future, most of the other tensions with the SM in the $b \to s$ data, in particular in the angular observables of the $B\to K^* \mu\mu$ decay and in the branching ratio of the $B_s \to \phi \mu\mu$ deca…

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Update on the b→s anomalies

We present a brief update of our model-independent analyses of the b->s data presented in the articles published in Phys. Rev. D96 (2017) 095034 and Phys. Rev. D98 (2018) 095027 based on new data on R_K by LHCb, on R_{K^*} by Belle, and on B_{s,d}-> mu^+ mu^- by ATLAS.

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Model independent analysis of the angular observables in B0→K*0μ+μ− and B+→K*+μ+μ−

We analyse the results recently presented on the $B^{+} \to K^{*+} \mu^+ \mu^-$ angular observables by the LHCb Collaboration which show indications for New Physics beyond the Standard Model. Within a model-independent analysis, we compare the fit results with the corresponding results for the angular observables in $B^{0} \to K^{*0} \mu^+ \mu^-$.

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Lepton nonuniversality in exclusive b→sℓℓ decays

The LHCb measurements of certain ratios of decay modes testing lepton flavor nonuniversality might open an exciting world of new physics beyond the standard model. The latest LHCb measurements of ${R}_{{K}^{*}}$ offer some new insight beyond the previous measurement of ${R}_{K}$. We work out the present significance for nonuniversality, and argue that claims of $5\ensuremath{\sigma}$ deviations from the standard model based on all present $b\ensuremath{\rightarrow}s{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ data including the ratios are misleading and are at present still based on guesstimates of hadronic power corrections in the $b\ensuremath{\rightarrow}s{\ensuremath{\el…

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On the anomalies in the latest LHCb data

Depending on the assumptions on the power corrections to the exclusive b -> s l+ l- decays, the latest data of the LHCb collaboration - based on the 3 fb^-1 data set and on two different experimental analysis methods - still shows some tensions with the SM predictions. We present a detailed analysis of the theoretical inputs and various global fits to all the available b -> s l+ l- data. This constitutes the first global analysis of the new data of the LHCb collaboration based on the hypothesis that these tensions can be at least partially explained by new physics contributions. In our model-independent analysis we present one-, two-, four-, and also five-dimensional global fits in th…

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Implications of the new LHCb angular analysis of B→K*μ+μ− : Hadronic effects or new physics?

The new angular analysis of the decay $B\ensuremath{\rightarrow}{K}^{*}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ recently presented by the LHCb Collaboration still indicates some tensions with the Standard Model predictions. There are several ongoing analyses to solve the problem of separating hadronic and new physics effects in this decay, but the significance of the observed tensions in the angular observables in $B\ensuremath{\rightarrow}{K}^{*}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ is still dependent on a theory guesstimate of the hadronic contributions to these decays. Using the new data from LHCb, we offer two tests which make a statistical compa…

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