论文标题
$ b_s \ for $ b_s \ to d_s \ellν_\ ell $的比率$ \ mathcal {r}（d_s）$通过在重夸克有效场理论的框架内使用QCD Light-Cone Sum规则
The ratio $\mathcal{R}(D_s)$ for $B_s \to D_s \ellν_\ell$ by using the QCD light-cone sum rules within the framework of heavy quark effective field theory
论文作者
论文摘要
在本文中，我们通过在重型夸克有效野外理论的框架内使用轻单元的总和来研究$ b_s \ to d_s $ transition形式。我们采用手性电流相关函数来进行计算，结果$ f _+^{b_s \ to d_s}（q^2）$和$ f_0^{b_s \ to d_s}（q^2）$主导了$ d_s $ -d_s $ d_s $ -d_s $ -Messon praditiond $ nife $ -messon $ -Messon $ -MESPLED $ - 同时$ -MESPENTE $ -MESPLED $ pression $ prestions $ nife prestions $ - Twist-3分布幅度受到极大抑制。在最大的后坐力点，我们获得$ f _ {+，0}^{b_s \ to d_s}（0）= 0.533^{+0.112} _ { - 0.094} $。通过在$ z $ series参数化方法的帮助下，将过渡形式进一步推断到所有物理上允许的$ q^2 $区域中，我们计算分支分数$ \ MATHCAL {b_s \ to d_s \ ell^ell^ell^\ ell^\ ell $ \ MATHCAL {b}（b_s \ to d_sτν_τ）$，给出$ \ Mathcal {r}（d_s）= 0.334 \ pm 0.017 $。
In the paper, we study the $B_s\to D_s$ transition form factors by using the light-cone sum rules within the framework of heavy quark effective field theory. We adopt a chiral current correlation function to do the calculation, the resultant transition form factors $f_+^{B_s\to D_s}(q^2)$ and $f_0^{B_s\to D_s}(q^2)$ are dominated by the contribution of $D_s$-meson leading-twist distribution amplitude, while the contributions from less certain $D_s$-meson twist-3 distribution amplitudes are greatly suppressed. At the largest recoil point, we obtain $f_{+,0}^{B_s \to D_s}(0)=0.533^{+0.112}_{-0.094}$. By further extrapolating the transition form factors into all the physically allowable $q^2$ region with the help of the $z$-series parametrization approach, we calculate the branching fractions $\mathcal{B}(B_s \to D_s \ell^\prime ν_{\ell^\prime})$ with $(\ell^\prime= e,μ)$ and $\mathcal{B}(B_s \to D_s τν_τ)$, which gives $\mathcal{R}(D_s)=0.334\pm 0.017$.
