Binary black holes (BBHs) have been observed through their gravitational wave (GW) emission in large numbers by LIGO, and particularly interesting cases have now started to arise. This includes the newly discovered GW190521, with both components in the mass-gap, a possible EM counterpart, and a non-zero eccentricity. At present, the astrophysical origin of the observed GW sources is not known. In case of GW190521 its possible EM counterpart points toward formation in a gas-rich environment, such as an AGN-disk; However, its measured eccentricity of about 0.7 remains a puzzle.
With this motivation, I will here present the first result on the possibility for forming eccentric LIGO sources in AGN-disk environments through strong few-body scatterings. Constraining the interactions to a 2-dimensional plane representing the disk geometry, I illustrate that when post-Newtonian (PN) corrections are included, the majority of the BBHs merge during their interaction, as opposed to after. This highly surprising result further implies that nearly all of the BBHs driven to merger through this process will appear eccentric in LIGO. This provides an independent hint that GW190521 formed dynamically in an AGN-disk.