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arXiv · 1104.1497

Rare B decays and Tevatron top-pair asymmetry

Chuan-Hung Chen·Sandy S. C. Law·Run-Hui Li
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Abstract

The recent Tevatron result on the top quark forward-backward asymmetry, which deviates from its standard model prediction by 3.4$σ$, has prompted many authors to build new models to account for this anomaly. Among the various proposals, we find that those mechanisms which produce $t\bar t$ via $t$- or $u$-channel can have a strong correlation to the rare B decays. We demonstrate this link by studying a model with a new charged gauge boson, $W'$. In terms of the current measurements on $B\to πK$ decays, we conclude that the branching ratio for $B^-\to π^- \bar K^0$ is affected most by the new effects. Furthermore, using the world average branching ratio for the exclusive B decays at $2σ$ level, we discuss the allowed values for the new parameters. Finally, we point out that the influence of the new physics effects on the direct CP asymmetry in B decays is insignificant.

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Chuan-Hung Chen, Sandy S. C. Law, Run-Hui Li. 2011-11-01. Rare B decays and Tevatron top-pair asymmetry. https://doi.org/10.1088/0954-3899%2F38%2F11%2F115008

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