论文标题
分支比率和$ cp $违反$ b \ tokπ$衰减的扰动QCD方法
Branching ratio and $CP$ violation of $B\to Kπ$ decays in a modified perturbative QCD approach
论文作者
论文摘要
我们根据$ k_ {t} $分解计算$ b \ tokπ$衰减的分支比率和$ cp $违规。横向动量的重新召集效果调节端点奇点。使用相对论潜在模型中获得的$ B $ MESON波函数，Sudakov因子不能有效地抑制软贡献。必须引入软尺度截止和软$ bk $，$bπ$和$kπ$。还考虑了来自顶点校正，夸克环和磁企鹅的最重要的临近级贡献。另外，包括颜色式辐射基质元素的贡献，它基本上是长距离动力学的。我们对分支比率和$ cp $违规的预测与实验数据非常吻合。尤其是$ cp $违反$ b^+\ to k^+π^0 $和$ b^0 \ to k^+π^ - $之间的巨大差异的理论结果与实验测量是一致的，因此，$kπ$ puzzle中的$kπ$ puzzle in $ b $衰减可以通过我们的修改函数求职QCD方法来解决。
We calculate the branching ratio and $CP$ violations for $B\to Kπ$ decays in a modified perturbative QCD approach based on $k_{T}$ factorization. The resummation effect of the transverse momentum regulates the endpoint singularity. Using the $B$ meson wave function that is obtained in the relativistic potential model, soft contribution cannot be suppressed effectively by Sudakov factor. Soft scale cutoff and soft $BK$, $Bπ$ and $Kπ$ form factors have to be introduced. The most important next-to-leading-order contributions from the vertex corrections, the quark loops, and the magnetic penguins are also considered. In addition, the contribution of the color-octet hadronic matrix element is included which is essentially of long-distance dynamics. Our predictions for branching ratios and $CP$ violations are in good agreement with the experimental data. Especially the theoretical result of dramatic difference between the $CP$ violations of $B^+\to K^+π^0$ and $B^0\to K^+π^-$ is consistent with experimental measurement, therefore the $Kπ$ puzzle in $B$ decays can be resolved in our way of the modified perturbative QCD approach.
