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arXiv · 2609.29295

The lepton flavor universality including the $b\rightarrow c l ν$ process in the $U(1)_X$SSM

Meng-Zi Cao·Shu-Min Zhao·Yue-Tong Liu·Shuang Di·Rong-Zhi Sun·Xing-Xing Dong
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Abstract

This paper calculates the lepton flavor universality including the $b\rightarrow c\ell ν$ process under the U(1) extension of the minimal supersymmetric standard model ($U(1)_X$SSM), and provides numerical analysis and summary. The numerical results are used to create one-dimensional and multi-dimensional plots to analyze the impacts of various parameters on the ratios $(\frac{R_{J/ψ}}{R^{SM}_{J/ψ}}$, $\frac{R_{{D}_s}}{R^{SM}_{D_s}}, \frac{R_{{D^*}_s}}{R^{SM}_{D^*_s}},\frac{R_{Λ_c}}{R^{SM}_{Λ_c}})$. The results show that several parameters have a certain effect on the ratios. Although it can't match the experimental data very well, with the right combination of parameter values, it can give better numerical results than the Standard Model. This shows that the $U(1)_X$SSM is very helpful for studying $b\rightarrow c\ell ν$ processes.

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Meng-Zi Cao, Shu-Min Zhao, Yue-Tong Liu, Shuang Di, Rong-Zhi Sun, Xing-Xing Dong. 2026-09-24. The lepton flavor universality including the $b\rightarrow c l ν$ process in the $U(1)_X$SSM. https://arxiv.org/abs/2609.29295

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