2025/11/26 by Qingyuan Liang, Ligong Bian, Liang, Qingyuan +5 · 2 citations
Physics and Astronomy · #Bayesian probability #Cosmology and Gravitation Theories #Detector #Electroweak interaction #Gravitational wave #Higgs boson #LIGO #Limit (mathematics) #Phase (matter) #Phase transition #Physics beyond the Standard Model #Pulsars and Gravitational Waves Research #Scalar (mathematics) #Singlet state #Stability (learning theory) #Standard Model (mathematical formulation) #Statistical Mechanics and Entropy #Theoretical and Computational Physics
paper · pdf · doi:10.1103/j5l2-hddr
openalex publication_date 2026/02/20 · openalex created_date 2026/02/21 · openalex updated_date 2026/05/21
We explore the prospects of probing the complex singlet extension of the Standard Model (CxSM) with gravitational waves from the electroweak phase transition. The study establishes a connection of the scalar potential parameters, the thermodynamic properties of the phase transition, with the directly measured stochastic gravitational-wave background in the presence of astrophysical background and foreground. Considering the space-based gravitational-wave detector Taiji, we construct a frequency-domain likelihood that incorporates instrumental and astrophysical noises, and we perform both Fisher-matrix forecasts and Bayesian nested sampling analysis. The comparison of these two approaches demonstrates consistent parameter recovery and highlights the sensitivity of Taiji to millihertz gravitational-wave signals. We further propagate the inferred constraints on the gravitational-wave spectrum back to the underlying CxSM parameters, obtaining meaningful limits on the Higgs self-couplings. The results emphasize the complementarity between gravitational-wave observations and collider measurements, showing that future missions such as Taiji can serve as a powerful probe of electroweak-scale new physics and the dynamical origin of the Higgs sector.