Dark matter, electroweak phase transition, and gravitational waves in the type II two-Higgs-doublet model with a singlet scalar field
Xiao-Fang Han (Department of Physics, Yantai University, Yantai 264005, People’s Republic of China); Lei Wang (Department of Physics, Yantai University, Yantai 264005, People’s Republic of China); Yang Zhang (ARC Centre of Excellence for Particle Physics at the Tera-scale, School of Physics and Astronomy, Monash University, Melbourne, Victoria 3800, Australia, School of Physics and Microelectronics, Zhengzhou University, ZhengZhou 450001, People’s Republic of China)
In the framework of the type II two-Higgs-doublet model with a singlet scalar dark matter , we study the dark matter observables, the electroweak phase transition, and the gravitational wave signals by such strongly first order phase transition after imposing the constraints of the LHC Higgs data. We take the heavy -even Higgs boson as the only portal between the dark matter and standard model (SM) sectors, and find that the LHC Higgs data and dark matter observables require and to be larger than 130 GeV and 360 GeV for in the case of the 125 GeV Higgs boson with the SM-like coupling. Next, we carve out some parameter space where a strongly first order electroweak phase transition can be achieved, and find benchmark points for which the amplitudes of gravitational wave spectra reach the sensitivities of the future gravitational wave detectors.
