Gas Assisted Binary Black Hole Formation in AGN Discs

Understand

We investigate close encounters by stellar mass black holes (BHs) in the gaseous discs of active galactic nuclei (AGN) as a potential formation channel of binary black holes (BBHs).

• We perform a series of 2D isothermal viscous hydrodynamical simulations within a shearing box prescription using the Eulerian grid code Athena++.
• We co-evolve the embedded BHs with the gas keeping track of the energetic dissipation and torquing of the BBH by gas gravitation and inertial forces.
• To probe the dependence of capture on the initial conditions, we discuss a suite of 345 simulations spanning local AGN disc density ($\rho_0$) and impact parameter ($b$) space.