New dark matter production mechanism and the gravitational wave signals
Fa Peng Huang
TL;DR
This work investigates non-thermal mechanisms for producing heavy dark matter, focusing on PBH evaporation/superradiance and first-order phase transitions as sources for candidates such as $pNGB$ DM, Q-balls, and filtered DM. By linking early-universe dynamics to gravitational-wave production, the authors propose a multi-messenger approach in which GW signals observable by facilities like LISA, TianQin, Taiji, and Cosmic Explorer accompany DM production signatures. Key contributions include modeling $pNGB$ DM from PBH processes with explicit symmetry-breaking potentials, outlining how PBHs can yield the correct relic density alongside induced GWs, and detailing FOPT-driven DM via (gauged) Q-balls with hydrodynamic effects shaping relic abundance and GW spectra. The work highlights a pathway to probe DM origin through GW astronomy, expanding the viable DM landscape beyond thermal freeze-out and enabling cross-checks across multiple next-generation detectors.
Abstract
The microscopic origin and production mechanism of dark matter (DM) remain central questions in cosmology and particle physics. While thermal freeze-out has long dominated DM model building, alternative non-thermal scenarios are gaining prominence. In this work, we explore novel production channels for heavy DM candidates, including pseudo-Nambu-Goldstone bosons (pNGBs), Q-balls, and filtered DM arising from early-universe phenomena such as primordial black hole (PBH) evaporation, superradiance, and first-order phase transitions. We demonstrate that these mechanisms naturally generate gravitational wave signals detectable by future observatories, such as LISA, TianQin, Taiji, and Cosmic Explorer. This multi-messenger approach offers a promising pathway to probe the origin and nature of DM beyond conventional paradigms.