Gravitational waves in the complex-singlet-extended Manohar-Wise model
Abstract
We investigate cosmological phase transitions and stochastic gravitational-wave signals in the Manohar-Wise model extended by a complex scalar singlet. Spontaneous breaking of a discrete Z3 symmetry produces domain walls, whose subsequent annihilation is driven by a small explicit symmetry-breaking bias. Subject to theoretical and experimental constraints, we study two thermal histories: a one-step strong first-order electroweak phase transition satisfying the baryon-number preservation criterion, and a two-step history whose first transition is a first-order transition along the singlet direction, leaving electroweak symmetry unbroken. We estimate the gravitational-wave contributions from sound waves, magnetohydrodynamic turbulence, and domain-wall annihilation. Within the adopted approximations, the phase-transition signals of the selected benchmarks peak at approximately 10^-3 -10^-2 Hz and overlap the projected sensitivity regions of space-based observatories such as LISA, TianQin, and BBO. Choosing the vacuum-energy bias to fix the domain-wall peak at approximately 2x10^-9 Hz, we find that the larger domain-wall tensions of the two-step benchmarks yield signals reaching the projected SKA sensitivity, whereas the one-step sample remains below the pulsar-timing sensitivities considered. These results illustrate the complementarity of millihertz and nanohertz gravitational-wave observations in probing phase transitions and discrete-symmetry breaking in this model.
Related
- Singlet Extended Mirror Standard Model World as Dark Matter and Gravitational Waves Imprints of a High Scale Mirror Phase Transitions
- Linking a 152 GeV diphoton excess to dark matter and gravitational waves in the singlet-extended 2HDM
- Probing the singlet-triplet scotogenic model with lepton flavor violation, gravitational waves and dark matter
- Self-lensing of gravitational waves from binary extreme-mass-ratio inspirals: Extended caustics and paired flashes
- Perturbative aspects of the electroweak phase transition with a complex singlet and implications for gravitational wave predictions
BibTeX
@misc{mei2026gravitational,
title = {{Gravitational waves in the complex-singlet-extended Manohar-Wise model}},
author = {Benhong Mei and Yabo Dong and Jun Fan and Jingya Zhu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.39781},
eprint = {2609.39781},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.39781},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Gravitational waves in the complex-singlet-extended Manohar-Wise model
AU - Benhong Mei
AU - Yabo Dong
AU - Jun Fan
AU - Jingya Zhu
PY - 2026
DA - 2026/09/30
PB - arXiv
DO - 10.48550/arxiv.2609.39781
UR - https://arxiv.org/abs/2609.39781
AB - We investigate cosmological phase transitions and stochastic gravitational-wave signals in the Manohar-Wise model extended by a complex scalar singlet. Spontaneous breaking of a discrete Z3 symmetry produces domain walls, whose subsequent annihilation is driven by a small explicit symmetry-breaking bias. Subject to theoretical and experimental constraints, we study two thermal histories: a one-step strong first-order electroweak phase transition satisfying the baryon-number preservation criterion, and a two-step history whose first transition is a first-order transition along the singlet direction, leaving electroweak symmetry unbroken. We estimate the gravitational-wave contributions from sound waves, magnetohydrodynamic turbulence, and domain-wall annihilation. Within the adopted approximations, the phase-transition signals of the selected benchmarks peak at approximately 10^-3 -10^-2 Hz and overlap the projected sensitivity regions of space-based observatories such as LISA, TianQin, and BBO. Choosing the vacuum-energy bias to fix the domain-wall peak at approximately 2x10^-9 Hz, we find that the larger domain-wall tensions of the two-step benchmarks yield signals reaching the projected SKA sensitivity, whereas the one-step sample remains below the pulsar-timing sensitivities considered. These results illustrate the complementarity of millihertz and nanohertz gravitational-wave observations in probing phase transitions and discrete-symmetry breaking in this model.
ER -