论文标题
分解和Sudakov在Leptonic辐射$ B $ decay中重新调整 - 重新评估
Factorization and Sudakov Resummation in Leptonic Radiative $B$ Decay -- A Reappraisal
论文作者
论文摘要
$ b $ -Meson Light-Cone分布幅度是许多独家衰减的振幅分解幅度的重要非扰动数量，例如$ b $ ersons，例如$ b^ - \toγ\，\ ell^ - \ ell^ - \barν$。我们重新考虑了该功能满足的重新归一化组（RG）方程，并在Laplace空间中的RG改良扰动理论中以近代领先顺序（NLO）介绍其解决方案，这是首次在动量空间和所谓的对角线（或双重）空间中。由于要描述$ b $衰减过程所需的信息，以$λ_ {\ rm qcd}/m_b $描述$λ_ {\ rm QCD}/m_b $最直接包含在发行的拉普拉斯空间中的分布幅度中，因此我们提出了一组未相关的hadronic parameters的无偏见的参数化。利用对重型电流运算符的三环异常尺寸的最新结果，我们得出了出现在$ b^ - \toγ\，\ ell^ - \ ell^ - \barν$ fractizization公式中的卷积积分表达式，该公式明确地独立于扩展，并且我们评估了（近似）nnlo的该公式。
The $B$-meson light-cone distribution amplitude is an important non-perturbative quantity arising in the factorization of the amplitudes for many exclusive decays of $B$ mesons, such as $B^-\toγ\,\ell^-\barν$. We reconsider the renormalization-group (RG) equation satisfied by this function and present its solution at next-to-leading order (NLO) in RG-improved perturbation theory in Laplace space and, for the first time, in momentum space and the so-called diagonal (or dual) space. Since the information needed to describe the $B$ decay processes at leading order in $Λ_{\rm QCD}/m_b$ is most directly contained in the distribution amplitude in Laplace space evaluated near the origin, we propose an unbiased parameterization of this object in terms of a small set of uncorrelated hadronic parameters. Using recent results on the three-loop anomalous dimension for heavy-light current operators, we derive an expression for the convolution integral appearing in the $B^-\toγ\,\ell^-\barν$ factorization formula that is explicitly scale independent, and we evaluate this formula at (approximate) NNLO.
