The form factors of Bc→ηc and Bc→J/ψ are analyzed in the framework of three-point QCD sum rules. In the calculations, the contributions of the vacuum condensate terms 〈gs2GG〉 and 〈gs3GGGf〉 are considered. In addition, the decay widths and branching ratios of several decay channels are predicted by using the calculated form factors. These decay processes include the nonleptonic decays Bc−→ηcπ−, ηcK−, ηcρ−, ηcK⁎−, J/ψπ−, J/ψK−, J/ψρ−, J/ψK⁎−, and the semileptonic decays Bc−→ηclν¯, J/ψlν¯. These results about the form factors and decay properties of Bc meson provide useful information for us to study the heavy-quark dynamics and find new physics beyond Standard Model.

中文翻译：

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系统分析 Bc → ηc、J/ψ 和相应的弱衰变的形状因子


在三点 QCD 和规则的框架中分析 Bc→ηc 和 Bc→J/ψ 的形状因子。在计算中，考虑了真空冷凝水项 〈gs2GG〉 和 〈gs3GGGf〉 的贡献。此外，通过使用计算出的 form factors来预测几个 decay 通道的衰减宽度和分支比率。这些衰变过程包括非轻子衰变 Bc−→ηcπ−、ηcK−、ηcρ−、ηcK⁎−、J/ψπ−、J/ψK−、J/ψρ−、J/ψK⁎−，以及半轻子衰变 Bc−→ηclν ̄、J/ψlν ̄。这些关于 Bc 介子的形状因子和衰变特性的结果为我们研究重夸克动力学和寻找标准模型之外的新物理学提供了有用的信息。