Microlensing of gravitational waves by dark matter structures

Understand

Gravitational lensing of gravitational waves provides a potential new probe of dark matter structures.

• In this work, we consider the microlensing effect on gravitational wave signals from black hole binaries induced by low-mass dark matter halos that do not retain enough baryonic matter to hold stars.
• We clarify systematically when this microlensing effect is relevant and study in detail its detectability by future gravitational wave observatories.
• We consider lensing by cold dark matter halos and by solitonic cores that reside in fuzzy dark matter halos.