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arXiv · 2501.01060

$S, T, U$ Parameters in The B-LSSM

Sheng-Kai Cui·Ke-Sheng Sun·Yu-Li Yan·Jin-Lei Yang·Tai-Fu Feng
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Abstract

Using the pinch technique, we compute the one-loop vertices of weak interactions in the B-LSSM and incorporate their pinch contributions into the gauge boson self-energies. Compared to the definitions of the $S, T,$ and $U$ parameters in the Standard Model based on the $SU(2)_L \otimes U(1)_Y$ group, the corresponding parameters in the local B-L gauge symmetry (B-LSSM) are modified. We provide these redefined $S, T,$ and $U$ parameters and demonstrate the convergence of the results. In the framework of the low-energy effective Lagrangian for weak interactions, the $S, T,$ and $U$ parameters can be expressed as functions of certain parameters in the B-LSSM. The updated experimental and fitting results constrain the parameter space of the B-LSSM strongly.

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Sheng-Kai Cui, Ke-Sheng Sun, Yu-Li Yan, Jin-Lei Yang, Tai-Fu Feng. 2025-01-02. $S, T, U$ Parameters in The B-LSSM. https://doi.org/10.1088/1674-1137%2Fae5590

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