Abstract:

Binary black hole mergers occurring within active galactic nucleus (AGN) disks have the potential to play a crucial role in the formation of stellar-mass binary black hole systems. However, the specific mechanisms leading to binary black hole mergers within AGN disks remain poorly understood. Nonetheless, it has been observed that the formation and merger rate of binaries in AGN disks exhibit remarkable efficiency, primarily attributed to the presence of a gaseous disk environment and frequent dynamical encounters. This study aims to demonstrate the suitability of AGN disks as ideal environments for black hole mergers. Through comprehensive numerical experiments utilizing a simplified yet accurate dynamics model, our findings reveal that this merger pathway within AGN disks can produce distinctive merger characteristics that are unlikely to arise from alternative merger channels. Consequently, the formation channel involving AGN disks emerges as a critically important pathway that has been overlooked in previous research.

Bio:
Yihan Wang is a postdoc fellow of NCfA (Nevada Center for Astrophysics) at UNLV (Independent, but he works mostly with Bing Zhang and Zhaohuan Zhu). Before he came to UNLV, he was a Ph.D. student at Stony Brook University working with Rosalba Perna. His research interests include tidal disruption events by solar mass black holes, gamma-ray bursts in dense environments, few-body dynamics with applications from supermassive black hole dynamics in galactic centers, to binary compact object mergers in AGN disks, to exoplanetary dynamics in dense star clusters.