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arXiv 0710.3818hep-ph
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研究B介子衰变的改进因子化方法

Improved Factorization Method in Studying B-meson Decays

Marina--Aura Dariescu, Ciprian Dariescu

摘要:

B衰变是一个积极的研究课题,因为它们提供了有用的信息,强和电弱相互作用的动力学测试的标准模型(SM)和模型超越,并非常适合于一个关键的分析CP破坏现象。在标准模型中,在SU(3)极限下,B衰变的CP破坏率差之间存在某些关系,例如$Δ(\bar{B}^0 \to π^+ π^-) = - Δ(\bar{B}^0 \to π^+ K^-)$。这封信的目的是研究一类过程中的直接CP破坏不对称性,在这类过程中,最近的理论进展,例如B衰变成两个轻的赝标量介子和轻的赝标量和轻矢量介子。利用Beneke { \it et al.}的QCD改进的因式分解模型,我们确定了标准模型中在SU(3)极限下有效的速率不对称之间的关系,并计算了它们的SU(3)破缺修正。最后,在某些过程中,例如$BR(B^- \to η^{\prime} K^-)$,我们声称,一个必须添加超对称贡献的威尔逊系数。在这些情况下,我们结束了一个$BR$取决于三个参数,其值由实验数据的约束。

英文摘要:

B decays are a subject of active research since they provide useful information on the dynamics of strong and electroweak interactions for testing the Standard Model (SM) and models beyond and are ideally suited for a critical analysis of CP violation phenomena. Within the standard model, there exist certain relations between CP violating rate differences in B decays in the SU(3) limit, as for example $Δ(\bar{B}^0 \to π^+ π^-) = - Δ(\bar{B}^0 \to π^+ K^-)$. The goal of this letter is to study the direct CP violation asymmetry in a class of processes where there has been recent theoretical progress, as for example the B decays into two light pseudoscalars mesons and into a light pseudoscalar and a light vector meson. We identify relations between rate asymmetries which are valid in the SU(3) limit in the standard model and we compute SU(3) breaking corrections to them, going beyond the naive factorization by using the QCD improved factorization model of Beneke {\it et al.}. Finally, in some processes as for example $BR(B^- \to η^{\prime} K^-)$, we claim that one has to add SUSY contributions to the Wilson coefficients. In these cases, we end with a $BR$ depending on three parameters, whose values are constrained by the experimental data.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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