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arXiv · 1407.7044

$SU(2)\times U(1)$ gauge invariance and the shape of new physics in rare $B$ decays

Rodrigo Alonso·Benjamin Grinstein·Jorge Martin Camalich
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Abstract

New physics effects in $B$ decays are routinely modeled through operators invariant under the strong and electromagnetic gauge symmetries. Assuming the scale for new physics is well above the electro-weak scale, we further require invariance under the full Standard-Model gauge symmetry group. Retaining up to dimension-6 operators, we unveil new constraints between different new-physics operators that are assumed to be independent in the standard phenomenological analyses. We illustrate this approach by analyzing the constraints on new physics from rare $B_{q}$ (semi-)leptonic decays.

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Rodrigo Alonso, Benjamin Grinstein, Jorge Martin Camalich. 2014-07-25. $SU(2)\times U(1)$ gauge invariance and the shape of new physics in rare $B$ decays. https://doi.org/10.1103/physrevlett.113.241802

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