Spin evolution and feedback of supermassive black holes in cosmological simulations

Understand

It is well established that the properties of supermassive black holes and their host galaxies are correlated through scaling relations.

• While hydrodynamical cosmological simulations have begun to account for the co-evolution of BHs and galaxies, they typically have neglected the BH spin, even though it may play an important role in modulating the growth and feedback of BHs.
• Here we introduce a new sub-grid model for the BH spin evolution in the moving-mesh code {\small AREPO} in order to improve the physical faithfulness of the BH modelling in galaxy formation simulations.
• We account for several different channels of spin evolution, in particular gas accretion through a Shakura-Sunyaev $\alpha$-disc, chaotic accretion, and BH mergers.