Gravitational Wave Emissions from First Order Phase Transitions with Two Component FIMP Dark Matter

Understand

We explore the emissions of the Gravitational Waves (GWs) from a strong first-order ekectroweak phase transition.

• To this end, a dark matter model has been investigated in Feebly Interacting Massive Particle (FIMP) scenario, where the dark matter particles are produced through "freeze-in" mechanism in the early Universe and due to their very small couplings they could not attain thermal and chemical equilibrium with the Universe's thermal plasma.
• In this context, we extend scalar sector of Standard Model of particle physics by two additional scalar singlets whose stability is protected by an unbroken discrete $Z_2 \times Z'_2$ symmetry and they are assumed to develop no VEV after spontaneous symmetry breaking.
• We study the first-order phase transition within the framework of this present model.