arXiv subjects

Meng-Zi Cao

Publications and source records attributed to Meng-Zi Cao.

3 recordsLinked to original sources

arXiv2026

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

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.

hep-ph↗

arXiv2026

Pair production of $h$ in the $U(1)_X$SSM

Higgs pair production provides an important probe of the Higgs self-interaction and the Higgs potential structure. We study the lightest neutral Higgs pair production process $gg \to hh$ via gluon fusion at the 14 TeV LHC, in the $U(1)_X$ supersymmetric standard model. As a $U(1)$ extension of the minimal supersymmetric standard model (MSSM), this model introduces new superfields that bring additional one-loop contributions to the production amplitude. We analyze the parameter dependence of the cross section numerically and present contour distributions in two-dimensional parameter planes. The results indicate that the gauge couplings $g_X$ and $g_{YX}$ are the most sensitive parameters, and the model yields sizable new physics corrections under current experimental constraints. This work helps to understand Higgs physics in the $U(1)_X$SSM and guides new physics searches at the high-luminosity LHC.

hep-ph↗

arXiv2026

Higgs Bosons at 95 and 125 GeV in the $U(1)_X$VLFM

We present a systematic analysis of the Higgs signal strengths at 125 GeV and 95 GeV in a non-supersymmetric $U(1)_X$ model with vector-like fermions ($U(1)_X$VLFM). This model extends the SM by introducing an additional $U(1)_X$ gauge symmetry, three right-handed neutrinos, two singlet Higgs fields ($ϕ$ and $S$), and one generation of vector-like quarks and leptons. The scalar fields mix with each other in the neutral CP-even sector, leading to two Higgs-like states around 95 GeV and 125 GeV. A $χ^2$ analysis is performed by combining the Higgs signal strength measurements at 125 GeV from ATLAS and CMS, including the $γγ$, $WW^*$, $ZZ^*$, $b\bar{b}$, and $τ\barτ$ channels, with the 95 GeV excesses observed in the diphoton and $b\bar{b}$ final states reported by CMS and LEP. Our results indicate that the $U(1)_X$VLFM can successfully reproduce the observed signal strengths of the 125 GeV Higgs while simultaneously explaining the 95 GeV excess. The parameters $g_X$, $g_{YX}$, $v_S$, $v_P$, and the new Yukawa couplings play a crucial role in achieving this consistency.

hep-ph↗