论文标题
重新访问辐射性leptonic $ b $衰减
Revisiting radiative leptonic $B$ decay
论文作者
论文摘要
在本文中，我们总结了求解领先的twist $ b $ -Meson LCDA的演化方程的现有方法。然后，在梅林空间中，我们在$ b \toγ\ ell维中以$ b \ to $ v \ellν$ decay in $λ/m_b $中的γ\ellν$衰减中的形式因素$ f_ {a，v} $进行了分解公式。此外，我们研究了抑制的当地贡献，可因素的非本地贡献（由$ 1/e_γ$和$ 1/m_b $抑制），以及对形式的软贡献。在采用两环级硬函数和JET功能的数值分析中，我们发现重新召集效应和功率校正都可以大大降低形式因素。最后，还计算了集成的分支比率，以与未来的实验数据进行比较。
In this paper, we summarize the existing methods of solving the evolution equation of the leading-twist $B$-meson LCDA. Then, in the Mellin space, we derive a factorization formula with next-to-leading-logarithmic (NLL) resummation for the form factors $F_{A,V}$ in the $B \to γ\ellν$ decay at leading power in $Λ/m_b$. Furthermore, we investigate the power suppressed local contributions, factorizable non-local contributions (which are suppressed by $1/E_γ$ and $1/m_b$), and soft contributions to the form factors. In the numerical analysis, which employs the two-loop-level hard function and the jet function, we find that both the resummation effect and the power corrections can sizably decrease the form factors. Finally, the integrated branching ratios are also calculated for comparison with future experimental data.
