Gravitational wave signatures from an extended inert doublet dark matter model

Abstract

We consider a particle dark matter model by extending the scalar sector of the Standard Model by an additional SU(2) scalar doublet which is made "inert" (and stable) by imposing a discrete Z 2 symmetry under which the additional scalar doublet is odd (and the SM is even) and it does not develop any vacuum expectation value (VEV). The lightest inert particle (LIP) of this inert doublet model (IDM) can be a viable candidate for Dark Matter. The IDM model is further extended by an additional singlet scalar which is also even under Z 2 and develop a VEV on spontaneous symmetry breaking. This additional scalar singlet mixes with SM Higgs and on diagonalisation of the mass matrix two CP even scalar eigenstates are obtained one of which is attributed to the physical Higgs (with mass 125 GeV). The LIP is the dark matter candidate in the extended model. For such a particle dark matter model we explore the first-order electroweak phase transition and consequent production of Gravitational Waves (GW) at that epoch of the early Universe and calculate the intensities and frequencies for such waves. We then investigate the detection possibilities of such GWs at the future spaceborne primordial GW detectors such as eLISA, BBO, ALIA, DECIGO, U-DECIGO and aLIGO.

Gravitational wave signatures from domain wall and strong first-order phase transitions in a two complex scalar extension of the Standard Model

“…Although the first-order electroweak (EW) phase transition (PT) would have been possible in the framework of SM of particle physics through the Higgs mechanism but with the observed Higgs mass of 125.09 GeV [34][35][36][37] the transition is a smooth cross-over and not a first-order one. However, in literature there are ample references where the authors have shown that SFOPT can be realised by simple extension of SM [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57]. In the present work however, we primarily explore GW emission from the annihilation of domain walls by proposing a simple extension of SM with two complex scalars.…”

“…In refs. [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] the authors have proposed different particle physics models for the production of GWs from first-order phase transition but variance from their approaches in this work, we consider an extension of SM with two complex scalars in such a way that it can provide GW production from SFOPT as well as the GW production from unstable domain walls. We constrain the model parameters by using some theoretical and experimental constraints such as vacuum stability, perturbativity and the collider bounds.…”

“…Vacuum Stability. The constraints on the parameter space from vacuum stability condition are obtained as [49,86]…”

Singlet-doublet fermionic dark matter and gravitational waves in a two-Higgs-doublet extension of the Standard Model

“…As mentioned in the Sec. I, GWs are produced from the FOPT majorly via three mechanisms namely, bubble collisions [66][67][68][69][70][71][72], sound wave [73][74][75][76] and turbulence in the plasma [77][78][79][80][81]. The total GW intensity Ω GW h 2 as a function of frequency can be expressed as the sum of the contributions from the individual components [66][67][68][69][70][71][72][73][74][75][76][77][78][79][80][81]:…”

“…The production of GW spectrum happens mainly via three processes: bubble collisions [66][67][68][69][70][71][72], sound wave [73][74][75][76] and turbulence in the plasma [77][78][79][80][81]. The signal thus produced can be detected in different GW detectors, for example, space-based detectors like Advanced Laser Interferometer Antenna (ALIA) [82], Big Bang Observer(BBO) [83], Deci-hertz Interferometer Gravitational wave Observatory (DECIGO) [84], Laser Interferometer Space Antenna(LISA) [85], groundbased detector advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO) [86] etc.…”