Gravitational Waves From Dark Sectors, Oscillating Inflatons, and Mass Boosted Dark Matter

TL;DR

This paper explores gravitational wave signals from scalar fields related to dark matter, phase transitions, and inflation, highlighting potential detection prospects and implications for dark matter mass enhancement.

Contribution

It introduces a simplified model linking dark matter, scalar fields, and gravitational waves, and analyzes their signatures from phase transitions and inflationary oscillations.

Findings

Gravitational wave spectra can reveal heavy dark sectors.

Scalar phase transitions can boost dark matter mass up to Planck scale.

Future observatories may detect these high-frequency gravitational waves.

Abstract

Gravitational waves signatures from dynamical scalar field configurations provide a compelling observational window on the early universe. Here we identify intriguing connections between dark matter and scalars fields that emit gravitational waves, either through a first order phase transition or oscillating after inflation. To study gravitational waves from first order phase transitions, we investigate a simplified model consisting of a heavy scalar coupled to a vector and fermion field. We then compute gravitational wave spectra sourced by inflaton field configurations oscillating after E-Model and T-Model inflation. Some of these gravitational wave signatures can be uncovered by the future Big Bang Observatory, although in general we find that MHz-GHz frequency gravitational wave sensitivity will be critical for discovering the heaviest dark sectors. Intriguingly, we find that scalars undergoing phase transitions, along with E-Model and T-Model potentials, can impel a late-time dark matter mass boost and generate up to Planck mass dark matter. For phase transitions and oscillating inflatons, the largest dark matter mass boosts correspond to higher amplitude stochastic gravitational wave backgrounds.