arXiv subjects

Shuang Di

Publications and source records attributed to Shuang Di.

6 recordsLinked to original sources

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

Lepton flavor violating decays $l_j \rightarrow l_i\gamma$ in the $U(1)_X$VLFM

In the $U(1)_X$ vector-like fermion model ($U(1)_X$VLFM), the Standard Model(SM) gauge group is extended with an additional $U(1)_X$ symmetry. Vector-like fermions and right-handed neutrinos are introduced, providing new sources of lepton flavor violation(LFV). In this paper, we perform a detailed study of the LFV decays $l_j \to l_i \gamma$ (with $j = \tau, \mu$; $i = \mu, e$; $i \neq j$) in this model. The numerical results show that, in certain parameter regions, the branching ratios of these processes can become large enough to be probed in future experiments. This work provides important theoretical guidance and constraints for exploring new physics beyond the SM.

hep-ph↗

arXiv2026

Calculation for Electric Dipole Moments of Lepton and Neutron in the N-B-LSSM via the Mass Insertion Approximation

In the N-B-LSSM, we calculate the electric dipole moments (EDMs) of lepton and neutron at the one loop level via the Mass Insertion Approximation (MIA). In the Standard Model (SM), charge parity (CP) violation originates only from the single phase of the Cabibbo-Kobayashi-Maskawa (CKM) matrix, and the predicted EDMs of lepton and neutron are far below the current experimental upper limits. Thus, EDMs serve as sensitive probes for exploring CP-violating phases in new physics. The N-B-LSSM extends the Minimal Supersymmetric Standard Model (MSSM) by introducing right-handed neutrino superfields and additional singlet Higgs superfields, which enriches the particle spectrum and the sources of CP violation. We derive the one loop analytical expressions for lepton and quark EDMs, and reveal their dependence on model parameters such as $g_{YB}$, $\theta_{\mu_H}$, $\theta_{1'}$, $\theta_{BB'}$ and $\tan\beta$. Numerical analyses demonstrate that within a reasonable parameter space, the EDMs of leptons (electron, muon, tau) and the neutron can satisfy the current experimental limitations. This study provides a systematic theoretical tool and numerical reference for exploring CP violation and new physics under the N-B-LSSM.

hep-ph↗

arXiv2025

Study of $\tau\rightarrow e M^+ M^-$ decays in the N-B-LSSM

Within the framework of the next to the minimal supersymmetric (SUSY) extension of the Standard Model (SM) with a local B-L gauge symmetry (N-B-LSSM), we study lepton flavor violating (LFV) $\tau\rightarrow e M^+ M^-$ decays: $\tau \rightarrow e \pi^+\pi^-$,~$\tau \rightarrow e \pi^+K^-$,~$\tau \rightarrow e K^+K^-$. According to the latest experimental data, the influence of different sensitive parameters on the branching ratios is considered. It can be seen from the numerical analysis that the main sensitive parameters and LFV sources are non-diagonal elements corresponding to the initial and final leptons. This work can provide a basis for discovering the existence of new physics (NP).

hep-ph↗

arXiv2025

One-loop corrections to the neutrino in the N-B-LSSM

In this paper, we study one-loop corrections to the neutrino mass matrix in the N-B-LSSM. We obtain the N-B-LSSM from the $U(1)$ extension of the minimal supersymmetric standard model(MSSM). By adding three generation right-handed neutrino superfields and three Higgs singlets, the model generates tiny neutrino masses at the tree level through the first type seesaw mechanism. However, one-loop corrections are essential for understanding neutrino masses and mixing angles. In our calculations, the one-loop corrections contribute approximately 10\% to the total result. We calculate the neutrino mass variance and mixing angle from both normal order neutrino mass spectrum and inverse order neutrino mass spectrum. Crucially, these corrections are 3-5 times larger than current experimental uncertainties. And they have implications for future neutrino oscillation experiments. This study provides new theoretical support for exploring the mechanism of neutrino mass generation in the supersymmetric model and provides clues for exploring new physics beyond the Standard Model (SM).

hep-ph↗

arXiv2024

A 95 GeV Higgs Boson in the $U(1)_X$SSM

The CMS and ATLAS Collaborations have recently reported their findings based on the comprehensive run 2 dataset, detailing their searches for a light Higgs boson with a mass of approximately 95 GeV. We investigate the excesses observed in the $\gamma\gamma$ and $b{\bar b}$ data at approximately 95 GeV in the $U(1)_X$ extension of the minimal supersymmetric standard model ($U(1)_X$SSM). Additionally, it also mixes with the SM-like Higgs boson. Research indicates that, in this model, identifying the mixture of the singlet Higgs states as the lightest Higgs boson holds tremendous potential for explaining the excess observed at approximately 95 GeV. In our calculations, we maintain the masses of the lightest and next-to-lightest Higgs bosons at approximately 95 GeV and 125 GeV, respectively. The study finds that the theoretical predictions for the signal strengths $\mu(h_{95})_{\gamma\gamma}$ and $\mu(h_{95})_{b{\bar b}}$ in the $U(1)_X$SSM align well with the excesses observed by CMS.

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