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arXiv · 2208.09675

Tree-level new physics in $R(K^{(*)})$

Jong-Phil Lee
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Abstract

We implement the $\chi^2$ fit for $R(K^{(*)})$ with possible tree-level new physics in a model-independent parametrization. Relevant Wilson coefficients are decomposed into the new physics scale, its power, and the fermionic couplings. Constraints from the branching ratio of $B_s\to\mu^+\mu^-$ can be naturally incorporated with the scheme. For a reasonable set of the parameter ranges it is found that the new physics is less than $\sim 5~{\rm TeV}$. Some new physics models including the leptoquark, $Z'$, etc. can be embraced within our framework. We give comments on new LHCb data which are close to the standard model predictions.

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Jong-Phil Lee. 2022-08-20. Tree-level new physics in $R(K^{(*)})$. https://arxiv.org/abs/2208.09675

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