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arXiv · 2503.11587

Penguin decays of B mesons

Abstract

We propose a set of optimized observables using penguin mediated $\bar{B}_d$ and $\bar{B}_s$ decays to $K^{(*)}\bar{K}^{(*)}$ and $K^*\phi$ final states that exhibhit a reduced sensitivity to power corrections than the corresponding branching ratios. Using these observables, branching ratios for the related vector-vector and pseudoscalar-pseudoscalar modes and branching ratios for modes involving other relevant pseudoscalar-vector final states ($K\phi$, $K^*\bar{K})$, we attempt to resolve the emergent combined pattern by assuming new physics contributions to the weak effective operators at the scale of the mass of the $b$ quark that are already present in the Standard Model. We find that the simplest scenario that can offer a simultaneous explanation is the two-operator scenario $Q_{4s,d}-Q_{6s,d}$. We briefly discuss how future experimental measurements may alter this picture and try to motivate such measurements for specific modes from our analysis.

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BibTeXRIS

Aritra Biswas. 2025-03-14. Penguin decays of B mesons. https://arxiv.org/abs/2503.11587

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