Contributions from the color-octet matrix elements to the $\overline{B}$ ${\to}$ ${\pi}{\pi}$ decays with QCD factorization approach

Yueling Yang; Bingbing Yang; Junfeng Sun

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arXiv · 2502.12461

Contributions from the color-octet matrix elements to the $\overline{B}$ ${\to}$ ${\pi}{\pi}$ decays with QCD factorization approach

Yueling Yang·Bingbing Yang·Junfeng Sun

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Abstract

Motivated by the ${\pi}{\pi}$ puzzle in nonleptonic $B$ decays in the time of high-precision and huge-data for particle physics, we restudy the $\overline{B}$ ${\to}$ ${\pi}{\pi}$ decays with QCD factorization approach. An additional contributions from the color-octet current matrix elements (COCME) which are unnoticed in almost all the previous calculation, are taken into consideration and parameterized by $X$. It is found that (1) form factor $F_{0}^{B{\pi}}$ ${\approx}$ $0.22$ is favored by the available latest measurements. (2) The COCME contributions are helpful to interpret the experimental data on branching ratios rather than $CP$ asymmetries for the $\overline{B}$ ${\to}$ ${\pi}{\pi}$ decays.

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Yueling Yang, Bingbing Yang, Junfeng Sun. 2025-02-18. Contributions from the color-octet matrix elements to the $\overline{B}$ ${\to}$ ${\pi}{\pi}$ decays with QCD factorization approach. https://arxiv.org/abs/2502.12461

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