Z penguins and rare B decays

Gino Isidori

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arXiv · hep-ph/0009024

Z penguins and rare B decays

Gino Isidori

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Abstract

Rare B decays of the type $b \to s~\ell^+\ell^-(ν\barν)$ are analyzed in a generic scenario where New Physics effects enter predominantly via $Z$ penguin contributions. We show that this possibility is both phenomenologically allowed and well motivated on theoretical grounds. The important role played in this context by the lepton forward-backward asymmetry in $B\to K^*\ell^+\ell^-$ is emphasized.

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Gino Isidori. 2000-09-04. Z penguins and rare B decays. https://arxiv.org/abs/hep-ph/0009024

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