论文标题
在包含半抑制的B衰减中的前向后不对称和部分力矩的差异
The forward-backward asymmetry and differences of partial moments in inclusive semileptonic B decays
论文作者
论文摘要
全球符合以包含半雌科$ b \ rightarrow x_clν_l$的运动矩的力矩,可以确定Cabibbo-kobayashi-Maskawa矩阵矩阵元素$ | v_ {cb} | $与非扰动的矩阵扩张元素一起。在当前拟合中,仅采用了两种不同的运动学分布,因此,需要考虑更高的这些分布的时刻来提取相关的非扰动矩阵元素。给定分布的力矩高度相关,实验不确定性增加了更高的矩。为了解决这些问题,Turczyk建议将带电的Lepton向前不对称$ \ Mathcal {a} _ {fb} $包含在全球拟合中,因为它提供了有关非扰动参数以外的非扰动参数的信息。 可以构建运动学分布的部分矩的差异,这些差异可以提供有关$ \ Mathcal {a} _ {fb} $以外的非扰动参数的其他信息,并首次在这项工作中进行了研究。此外,研究了四摩梅氏菌转移方块上的实验切割,并证明可以保留角度分布的形状,与Lepton能量上的常用切割相反。最后,讨论了最终状态辐射和实验性Lepton识别要求对$ \ Mathcal {a} _ {fb} $的测量以及部分矩的差异的影响。
Global fits to moments of kinematic distributions measured in inclusive semileptonic $B\rightarrow X_c l ν_l$ enable the determination of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{cb}|$ together with non-perturbative matrix elements of the heavy quark expansion. In current fits, only two distinct kinematic distributions are employed and, as a consequence, higher moments of these distributions need to be taken into account to extract the relevant non-perturbative matrix elements. The moments of a given distribution are highly correlated and experimental uncertainties increase for higher moments. To address these issues, Turczyk suggested the inclusion of the charged lepton forward-backward asymmetry $\mathcal{A}_{FB}$ in global fits, since it provides information on non-perturbative parameters beyond the commonly used moments. It is possible to construct differences of partial moments of kinematic distributions, which can provide additional information on the non-perturbative parameters beyond $\mathcal{A}_{FB}$ and are studied in this work for the first time. Further, experimental cuts on the four-momentum transfer square are studied and are shown to preserve the shape of the angular distribution, in contrast to commonly used cuts on the lepton energy. Finally, the impact of final-state radiation and experimental lepton identification requirements on measurements of $\mathcal{A}_{FB}$ and differences of partial moments are discussed.