Speaker
Description
Microlensing surveys targeting the stellar fields of the Magellanic Clouds, the Galactic Bulge, and M31 have long constrained the abundance of Massive Compact Halo Objects (MACHOs) and galactic halo structure. Just as electromagnetic radiation is gravitationally lensed, so too are gravitational waves (GWs) producing repeated or chromatically distorted signals. For short-lived transient sources such as compact binary mergers, the relative motion between source, lens, and detector can safely be ignored.
Continuous gravitational waves (CGWs) are undetected signals, sustaining over timescales comparable to or exceeding full observing runs. Candidate sources include rotating asymmetric neutron stars, inspiralling compact binaries, and ultralight boson clouds around black holes. For CGWs, source-lens-detector motion can no longer be neglected and lensing results in time-varying amplitude magnification and SNR modulation, producing a GW analogue of the optical Paczyński curve.
In this work, we model the lensing signatures of CGWs across a range of dark matter profiles, including bare and dressed primordial black holes and self-interacting dark matter. We show that these signatures not only boost detectability through amplitude magnification, but also carry distinguishable imprints of the underlying dark matter distribution opening new observational avenues for discriminating between warm and cold dark matter scenarios.