Academia Sinica Logo

【Abstract】

We present a comprehensive study on the complex dynamics of black hole accretion processes, covering stellar and galactic scales. Focusing on hot coronal flows, regions of high-energy emission in black holes of all sizes, we examine two cases: a stellar mass & a supermassive black hole. For the stellar-mass black hole, we use relativistic hydrodynamic simulations to investigate short-timescale X-ray variability (<100 s) in Cygnus X-1, attributing it to clumpy, wind-fed accretion from its binary companion. Our model shows oscillatory shock behavior consistent with observed hard X-ray spectra. We employ GRMHD simulations for the SMBH to study cold chaotic accretion dynamics in M87. By exploring the interactions between turbulent cold gas motions, angular momentum cancellation, and thermalization processes, we aim to understand the feeding mechanisms of supermassive black holes in galactic centers. This research bridges the micro- and macroscopic scales of black hole accretion physics, shedding light on the intricate relationship between accretion phenomena and galaxy evolution.