报告摘要：Supermassive black hole (SMBH) binaries within galaxy mergers are the primary target for low-frequency gravitational wave (GW) observatories. Understanding the coalescence process of SMBH binaries in a cosmological context is critical for accurate GW predictions. However, traditional galaxy formation simulations often merge SMBHs instantaneously at kpc or sub-kpc separation scales due to resolution limitations, leading to significant uncertainty in estimating SMBH coalescence time-scales. In this talk, I will introduce the KETJU code, a newly developed numerical tool capable of simultaneously following galaxy (hydro-)dynamics and resolving SMBH dynamics with post-Newtonian corrections down to a few tens of Schwarzschild radii. This numerical tool enables us to improve the estimation of the SMBH merger time-scales, especially in gas-rich galaxy mergers, and study the impact of SMBH dynamics on galaxy properties.

主讲人简介：Dr. Shihong Liao obtained his PhD from the Chinese University of Hong Kong and subsequently conducted postdoctoral research at the National Astronomical Observatories, CAS (NAOC) and the University of Helsinki. He is currently an associate researcher at NAOC. His research focuses on galaxy formation, supermassive black holes, and cosmological simulations.