Motivated by recent experimental results on \( R_{K^{(*)}}\) and \(\mathcal {P}^{\prime }_{5}\) in B → K^(∗)ℓ⁺ℓ⁻ and the latest improved measurement result in Λ_b →Λℓ⁺ℓ⁻ processes. We will investigate the rare decay on the flavor-changing neutral current process of Λ_b baryon and B meson in the family non-universal \(Z^{\prime }\) model, which is one of the well motivated extensions of the Standard Model. We have obtained the upper limits on the NP coupling parameters from the recent experimental measurements of the decay processes B_s → ℓ⁺ℓ⁻ B → K^(∗)ℓ⁺ℓ⁻, B → X_sℓ⁺ℓ⁻ and Λ_b →Λℓ⁺ℓ⁻. Then we analyze the branching ratio, the normalized forward-backward asymmetries and a series of angular observables in the Standard Model and family non-universal \(Z^{\prime }\) model. We find that the constrained NP coupling parameters have few obvious effects on the process b → sμ⁺μ⁻, nevertheless, NP coupling parameters have very large effects on the process b → sτ⁺τ⁻. In the future we expect the precision measurements of these observables will be researched by LHCb and Belle-II.

通过最近的实验结果上的动机\（R_ {K ^ {（*）}} \）和\（\ mathcal {P} ^ {\素} _ {5} \）在乙→ ķ ^（*）ℓ ⁺ ℓ ^-和最新的改进的测量结果在Λ _b →交通Λ ℓ ⁺ ℓ ^-进程。我们将探讨的味道改变中性流过程中的稀有衰变Λ _b重子和B介子在家庭非通用\（Z ^ {\黄金} \）模型，这是标准模型的良好动机扩展之一。我们已获得来自最近衰变的实验测量的NP耦合参数的上限过程乙_小号→ ℓ ⁺ ℓ ^- 乙→ ķ ^（*）ℓ ⁺ ℓ ^- ，乙→ X_小号ℓ ⁺ ℓ ^-和Λ _b → Λ ℓ ⁺ ℓ ^-。然后，我们分析了标准模型和族非通用\（Z ^ {\ prime} \）模型中的分支比，归一化的前后不对称性和一系列角度可观量。我们发现，受约束的NP耦合参数对过程有几个明显的效果b →小号μ ⁺ μ ^-尽管如此，NP耦合参数对过程有非常大的影响b →小号τ ⁺ τ ^- 。将来，我们预计LHCb和Belle-II将研究这些可观测物的精度测量。