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Branching ratio and CP asymmetry of $B_s \to π^+ π^-$ decays in the perturbative QCD approach

Ying Li·Cai-Dian Lu·Zhen-Jun Xiao·Xian-Qiao Yu
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Abstract

In this paper, we calculate the decay rate and CP asymmetry of the $B_s \to π^+π^-$ decay in perturbative QCD approach with Sudakov resummation. Since none of the quarks in final states is the same as those of the initial $B_s$ meson, this decay can occur only via annihilation diagrams in the standard model. Besides the current-current operators, the contributions from the QCD and electroweak penguin operators are also taken into account. We find that (a) the branching ratio is about $4 \times 10^{-7}$; (b) the penguin diagrams dominate the total contribution; and (c) the direct CP asymmetry is small in size: no more than $3% $; but the mixing-induced CP asymmetry can be as large as ten percent testable in the near future LHC-b experiments.

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Ying Li, Cai-Dian Lu, Zhen-Jun Xiao, Xian-Qiao Yu. 2004-05-24. Branching ratio and CP asymmetry of $B_s \to π^+ π^-$ decays in the perturbative QCD approach. https://doi.org/10.1103/physrevd.70.034009

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