Constraining binary mergers in AGN disks using the non-observation of lensed gravitational waves

Understand

The dense and dynamic environments within active galactic nuclei (AGN) accretion disks may serve as prolific birthplaces for binary black holes (BBHs) and one possible origin for some of the BBHs detected by gravitational-wave (GW) observatories.

• We show that a considerable fraction of the BBH in AGN disks will be strongly lensed by the central supermassive black hole (SMBH).
• Thus, the non-observation of lensed GW signals can be used to constrain the fraction of BBH binaries residing in AGN disks.
• The non-detection of lensing with current ${\cal O}(100)$ detections will be sufficient to start placing constraints on the fraction of BBHs living within accretion disks near the SMBH.