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Yu-Li Yan

Publications and source records attributed to Yu-Li Yan.

9 recordsLinked to original sources

The Muon and Tau Electric Dipole Moments in the B-L Supersymmetric Standard Model

Recently proposed experiments are expected to significantly improve the measurement sensitivities of the electric dipole moments (EDMs) of muon ($d_\mu$) and tau ($d_\tau$). Given that theoretical predictions for $d_\mu$ and $d_\tau$ typically surpass those for the electron EDM, this work focuses on studying the contributions from the CP-violating (CPV) effects in the B-L supersymmetric (SUSY) standard model (B-LSSM) to $d_\mu$ and $d_\tau$. After considering the corrections from some two-loop diagrams, the contributions in the B-LSSM to the EDMs of charged leptons are presented analytically in general forms. The numerical results show that the traditional $\mu$-term in most SUSY models makes dominant contributions to $d_\mu$ and $d_\tau$, while the B-LSSM specific CPV parameters also induce significant effects. It is found that across a substantial region of the B-LSSM parameter space, $d_\mu$ falls well within the projected sensitivity at Phase II of the proposed experiment, and $|d_\tau|$ can reach about $10^{-21}e\cdot\text{cm}$.

hep-ph

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

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.

hep-ph

$e^{+}e^-\rightarrow hhZ$ in the B-L symmetric SSM

The double Higgs boson production through $e^{+}e^-\rightarrow hhZ$ is analyzed in the minimal supersymmetric extension of the Standard Model(SM) with the local gauge symmetry $U(1)_{B-L}$, where $h$ denotes the lightest Higgs boson with 125 GeV. Considering the constraints from the updated prediction data, we find that the production cross section of this process in the model depends on some parameters strongly.

hep-ph

Lepton-flavor violation and two loop electroweak corrections to $(g-2)_μ$ in the B-L symmetry SSM

Charged lepton flavor violating processes are forbidden in the standard model (SM), hence the observation of charged lepton flavor transitions would represent a clear signal of new physics beyond the standard Model. In this work, we investigate some lepton flavor violating processes in the minimal supersymmetric extension of the SM with local $B-L$ gauge symmetry (B-LSSM). And including the corrections from some two loop diagrams to the anomalous dipole moments (MDM) of muon, we discuss the corresponding constraint on the relevant parameter space of the model. Considering the constraints from updated experimental data, the numerical results show that, new contributions in the B-LSSM enhance the MSSM predictions on the rates of $l_j-l_i$ transitions about one order of magnitude, and also enhance the MSSM prediction on the muon MDM. In addition, two loop electroweak corrections can make important contributions to the muon MDM in the B-LSSM.

hep-ph

Neutrino masses in the minimal gauged $(B-L)$ supersymmetry

We present the radiative corrections to neutrino masses in a minimal supersymmetric extension of the standard model with local $U(1)_{B-L}$ symmetry. At tree level, three tiny active neutrinos and two nearly massless sterile neutrinos can be obtained through the seesaw mechanism. Considering the one-loop corrections to the neutrino masses, the numerical results indicate that two sterile neutrinos obtain ${\rm KeV}$ masses and the small active-sterile neutrino mixing angles. The lighter sterile neutrino is a very interesting dark matter candidate in cosmology. Meanwhile the active neutrinos mixing angles and mass squared differences agree with present experimental data.

hep-ph

125 GeV Higgs decay with lepton flavor violation in the $μν$SSM

Recently, the CMS and ATLAS Collaborations have reported direct searches for the 125 GeV Higgs decay with lepton flavor violation, $h\rightarrow μτ$. In this work, we analyze the signal of the lepton flavour violating (LFV) Higgs decay $h\rightarrow μτ$ in the $μ$ from $ν$ Supersymmetric Standard Model ($μν$SSM) with slepton flavor mixing. Simultaneously, we consider the constraints from the LFV decay $τ\rightarrow μγ$, the muon anomalous magnetic dipole moment and the lightest Higgs mass around 125 GeV.

hep-ph

$B_{s,d}^0\rightarrow l^+l^-$ in the minimal gauged $(B-L)$ supersymmetry

Complete expressions of effective Hamilton for $b\rightarrow sl^+l^-\;(l=μ,\;τ)$ are derived in the framework of minimal supersymmetric extension of the standard model with local $B-L$ gauge symmetry. With some assumptions on parameters of the model, a numerical analysis of the supersymmetric contributions to the branching ratios of $B_s^0\rightarrow l^+l^-\;(l=μ,\;τ)$ is presented.

hep-ph

Spontaneous R-parity violation in the minimal gauged $(B-L)$ supersymmetry with a $125\;{\rm GeV}$ Higgs

We precisely derive the mass squared matrices for charged and neutral (CP-odd and CP-even) Higgs, as well as the mass matrices for neutrino-neutralino and charged lepton-chargino in the minimal R-parity violating supersymmetry with local $U(1)_{B-L}$ symmetry. In the framework the nonzero TeV scale vacuum expectations of right-handed sneutrinos induce the heavy mass of neutral $U(1)_{B-L}$ gauge boson, and result in relatively large mixing between the lightest CP-even Higgs and three generation right-handed sneutrinos when we include the one-loop corrections to the scalar potential. We numerically show that there is parameter space of the considered model to accommodate experimental data on the newly ones of Higgs signal from LHC and experimental observations on the neutrino oscillation simultaneously.

hep-ph

Gauged baryon and lepton numbers in supersymmetry with a $125\;{\rm GeV}$ Higgs

Assuming that the Yukawa couplings between the Higgs and exotic quarks cannot be ignored, we analyze the signals of decay channels $h\rightarrowγγ$ and $h\rightarrow VV^*\;(V=Z,\;W)$ with the Higgs mass around $125\;{\rm GeV}$ in a supersymmetric extension of the standard model where baryon and lepton numbers are local gauge symmetries. Adopting some assumptions on relevant parameter space, we can account for the experimental data on Higgs from ATLAS and CMS naturally.

hep-ph