Revisiting $K\pi$ puzzle in the pQCD factorization approach

Abstract

In this paper, we calculated the branching ratios and direct CP violation of the four $B\to K\pi$ decays with the inclusion of all currently known next-to-leading order (NLO) contributions by employing the perturbative QCD (pQCD) factorization approach. We found that (a) Besides the 10% enhancement from the NLO vertex corrections, the quark-loops and magnetic penguins, the NLO contributions to the form factors can provide an additional $\sim 15$ enhancement to the branching ratios, and lead to a very good agreement with the data; (b) The NLO pQCD predictions are ${\text{acp}}^{dir}(B^0\to K^{+}{\pi }^{-})=(-6.5\pm 3.1)$ and ${\text{acp}}^{dir}(B^{+}\to K^{+}{\pi }^0)=(2.2\pm 2.0)$, become well consistent with the data due to the inclusion of the NLO contributions.

Comments: 11 pages, 2 pdf figures. to be published in Chinese Physics C; several typos removed