AI 中文总结
本文在QCD求和规则框架下分析了双重重子$\mathcal{B}_{Q_{1}Q_{2}}$到$\mathcal{B}_{Q_{1}}^{*}$的半轻子衰变过程，计算了相关形式因子并预测了多种物理量。
AI 中文摘要
在QCD求和规则框架下，我们系统分析弱过渡过程$\mathcal{B}_{Q_{1}Q_{2}}(\frac{1}{2}^{+})\rightarrow\mathcal{B}_{Q_{1}}^{*}(\frac{3}{2}^{+})$。在QCD侧进行操作乘积展开时，我们考虑了扰动部分和真空凝聚项直至维数6的贡献。在现象学侧，我们通过使用16种不同的狄拉克结构消除低自旋态和负宇称态的干涉。作为应用，这些形式因子最终被用来分析$\mathcal{B}_{Q_{1}Q_{2}}(\frac{1}{2}^{+})\rightarrow\mathcal{B}_{Q_{1}}^{*}(\frac{3}{2}^{+})l\nu$的半轻子衰变，这些衰变由过渡过程$c\rightarrow d/s+l^{+}+\nu_{l}$和$b\rightarrow u+l^{-}+\overline{\nu}_{l}$驱动。预测的物理量不仅包括部分宽度、$\Gamma_{L}/\Gamma_{T}$比值和分支比，还包括一些可观测量，如轻子的前向-后向不对称参数$A_{FB}^{l}$、子双重重子的极化矢量的$P_z^{F}$分量以及轻子的纵向极化$P_z^{l}$。我们希望所有这些关于弱衰变的理论预测将有助于未来实验研究双重重子的性质。
英文摘要
In the framework of QCD sum rules, we systematically analyze the weak transition process $\mathcal{B}_{Q_{1}Q_{2}}(\frac{1}{2}^{+})\rightarrow\mathcal{B}_{Q_{1}}^{*}(\frac{3}{2}^{+})$. When doing the operator product expansion in the QCD side, we consider the contributions of perturbative part and vacuum condensate terms up to dimension 6. In the phenomenological side, we eliminate the interferences of the low spin states and negative parity states by employing 16 different dirac structures. As an application, these form factors are finally used to analyze the semileptonic decays of $\mathcal{B}_{Q_{1}Q_{2}}(\frac{1}{2}^{+})\rightarrow\mathcal{B}_{Q_{1}}^{*}(\frac{3}{2}^{+})lν$, where these decays are driven by the transition processes $c\rightarrow d/s+l^{+}+ν_{l}$ and $b\rightarrow u+l^{-}+\overlineν_{l}$. The predicted physical quantities include not only the partial widths, ratios of $Γ_{L}/Γ_{T}$ and the branching fractions, but also some observables such as the forward-backward asymmetry parameter $A_{FB}^{l}$ of lepton, the $P_z^{F}$ component of the polarization vector for daughter baryon and the longitudinal polarization of the lepton $P_z^{l}$. We hope all of these theoretical predictions about the weak decays will be helpful for studying the properties of doubly heavy baryons in experiments in the future.
