Implication of nano-Hertz stochastic gravitational wave on dynamical dark matter through a first-order phase transition

Abstract

For the first time, the expected stochastic gravitational wave background is probably discovered after observing the Hellings Downs correlation curve by several pulsar timing array (PTA) collaborations around the globe including NANOGrav, European PTA, Parkes PTA, and Chinese PTA. These new observations can help to explore the dark matter formation mechanisms in the early universe. We study the implication of those results on the dynamical dark matter formation mechanisms through first-order phase transition in the early universe. Both the Q-ball dark matter and super-cool dark matter are investigated in the strong super-cooling phase transition which are consistent with the observed stochastic gravitational wave background.Comment: 22 pages, 6 figures, 1 table; comments are welcom