Probing ultralight dark matter with future ground-based gravitational-wave detectors

Understand

Ultralight bosons are possible fundamental building blocks of nature, and promising dark matter candidates.

• They can trigger superradiant instabilities of spinning black holes (BHs) and form long-lived "bosonic clouds" that slowly dissipate energy through the emission of gravitational waves (GWs).
• Previous studies constrained ultralight bosons by searching for the stochastic gravitational wave background (SGWB) emitted by these sources in LIGO data, focusing on the most unstable dipolar and quadrupolar modes.
• Here we focus on scalar bosons and extend previous works by: (i) studying in detail the impact of higher modes in the SGWB; (ii) exploring the potential of future proposed ground-based GW detectors, such as the Neutron Star Extreme Matter Observatory, the Einstein Telescope and Cosmic Explorer, to detect this SGWB.