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arXiv · 1506.02398

Constrain the UT angle $γ$ by CP violation parameters in $B^0 \to π^+ π^-$

Qin Qin·Zhi-Tian Zou·Cai-Dian Lü·Ying Li
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Abstract

We calculate the tree and penguin amplitudes in the $B^0\toπ^+π^-$ decay channel employing the perturbative QCD factorization approach. Using the amplitudes as input with the theoretical uncertainties sufficiently considered, we constrain the UT angle $γ$ to $53^\circ\leqγ\leq70^\circ$, from the measurements of the CP violation parameters $C_{π^+π^-}$ and $S_{π^+π^-}$ in $B^0\toπ^+π^-$. The U-spin breaking effect between $B^0\toπ^+π^-$ and $B_s^0\to K^+K^-$ is estimated to be around 30\%.

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Qin Qin, Zhi-Tian Zou, Cai-Dian Lü, Ying Li. 2015-06-26. Constrain the UT angle $γ$ by CP violation parameters in $B^0 \to π^+ π^-$. https://doi.org/10.1088/1674-1137%2F40%2F3%2F031001

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