arXiv subjects

Mei-Shu-Yu Wang

Publications and source records attributed to Mei-Shu-Yu Wang.

4 recordsLinked to original sources

arXiv2026

Prospects for probing neutral vector-like leptons via pair production at muon collider

Vector-like leptons (VLLs) are well-motivated candidates for physics beyond the Standard Model. We investigate the sensitivity of the $6$ TeV muon collider to the neutral doublet VLL (denoted as $N$) via its pair production within a general VLL framework. Taking vector-like muon as a case study, we study the subsequent decay $N\rightarrow W^+ μ$ and analyze two representative signals, namely $4j2μ$ and $2\ell2μE\mkern-10.5 mu/$, arising from the hadronic and leptonic decays of the $W$ boson, respectively. The signal and background events are simulated within a complete Monte Carlo framework, and a cut-based analysis is performed at the $6$ TeV muon collider with an integrated luminosity $\mathcal{L}=4$ ab$^{-1}$ and beam polarizations $(P_{μ^+},P_{μ^-})=(-1,1)$. We consider VLL masses in the range of $1300-3000$ GeV and evaluate the corresponding search sensitivity. Our results show that the future $6$ TeV muon collider can effectively probe neutral doublet VLLs through the $4j2μ$ and $2\ell2μE\mkern-10.5 mu/$ signals, with statistical significances exceeding $5σ$ over a broad mass range. These results demonstrate that the future $6$ TeV muon collider has excellent potential to search neutral doublet VLLs.

hep-ph↗

arXiv2026

Searching for long-lived axion-like particles via displaced vertices at the HL-LHC

Axion-like particles (ALPs) are well-motivated extensions of the standard model (SM) that appear in numerous new physics scenarios. In this paper, we concentrate on searches for long-lived ALPs predicted by the photophobic scenario at the HL-LHC with the center-of-mass energy $\sqrt{s}=14$ TeV and the integrated luminosity $\mathcal{L}=$ $3$ ab$^{-1}$. We consider the process $pp \to γa$ with the ALP $a$ decaying into a pair of displaced charged leptons and perform a detailed analysis of two types of signals: $π^+ π^- γE\mkern-10.5 mu/_T $ and $\ell^+ \ell^- γE\mkern-10.5 mu/_T $. For the $π^+ π^- γE\mkern-10.5 mu/_T $ signal, we find that the prospective sensitivities of the HL-LHC can reach $g_{aWW}\in [8.72 \times 10^{-3}, 6.42 \times 10^{-2}]$ TeV$^{-1}$ for the ALP mass $m_a \in [4, 10]$ GeV. While for the $\ell^+ \ell^- γE\mkern-10.5 mu/_T $ signal, the HL-LHC can probe a broader parameter space, with the sensitivities covering $m_a \in [4, 10]$ GeV and $g_{aWW} \in [4.17 \times 10^{-3}, 2.00 \times 10^{-1}]$ TeV$^{-1}$. These long-lived searches complement some previous prompt decay studies from LEP and LHC experiments, extending the parameter space explored by the LHCb collaboration. Our results show that the HL-LHC has significant potential to probe long-lived ALPs via their displaced vertex signatures.

hep-ph↗

arXiv2025

Probing the couplings of an axion-like particle with leptons via three-lepton final state processes at future $e^{-}p$ colliders

The axion-like particle (ALP) is one of the best motivated particles beyond the Standard Model (SM). We explore the possibility of detecting the couplings of ALP with leptons via three-lepton final state processes $e^- p \to e^- j a~(a \to \ell^+ \ell^-)$ at the LHeC (FCC-eh). For completeness, we investigate the cases where the ALP decays not only into electron and muon pairs but also into tau pairs, and perform a detailed simulation for the decays of taus. We find that the prospective sensitivities of the LHeC (FCC-eh) with the center-of-mass energy $\sqrt{s}=1.3~(3.5)$ TeV and the integrated luminosity $\mathcal{L}=1~ (2)$ ab$^{-1}$ to the ALP-lepton couplings are not only stronger than some existing bounds of the LHC and LEP but also complementary to the expected bounds of the CEPC and FCC-ee.

hep-ph↗

arXiv2024

Searching for the light leptophilic gauge boson $Z_x$ via four-lepton final states at the CEPC

We investigate the possibility of detecting the leptophilic gauge boson $Z_x$ predicted by the $U(1)_{L_e-L_μ}$ model via the processes $e^+e^-\rightarrow\ell^+\ell^-Z_x(Z_x\rightarrow \ell^+\ell^-)$ and $e^+e^-\rightarrow \ell^+\ell^-Z_x(Z_x\rightarrow ν_\ell\bar{ν_\ell})$ at the Circular Electron Positron Collider (CEPC) with the center of mass energy $\sqrt s=240$ GeV and the luminosity $\mathcal{L}=5.6$ $\mathrm{ab^{-1}}$. We give the expected sensitivities of the CEPC to the parameter space at $1σ$, $2σ$, $3σ$ and $5σ$ levels.

hep-ph↗