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$B^0 \to ϕϕ$ Decay in Perturbative QCD Approach

Cai-Dian Lü·Yue-long Shen·Jin Zhu
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Abstract

The rare decay $B^0 \to ϕϕ$ can occur only via penguin annihilation topology in the standard model. We calculate this channel in the perturbative QCD approach. The predicted branching ratio is very small at ($10^{-8}$). We also give the polarization fractions, which shows that the transverse polarization contribution is comparable to the longitudinal one, due to a big transverse contribution from factorizable diagrams. The small branching ratio in SM, makes it sensitive to any new physics contributions.

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Cai-Dian Lü, Yue-long Shen, Jin Zhu. 2005-05-14. $B^0 \to ϕϕ$ Decay in Perturbative QCD Approach. https://doi.org/10.1140/epjc%2Fs2005-02199-7

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