Active Galactic Nuclei Feedback in an Elliptical Galaxy with the Most Updated AGN Physics (II): High-Angular Momentum Case

TL;DR

This study uses high-resolution simulations to explore how active galactic nuclei feedback affects elliptical galaxy evolution when the galaxy's gas has high angular momentum, updating models with recent AGN physics.

Contribution

It introduces a new simulation approach incorporating the latest AGN physics and models the impact of high angular momentum on galaxy evolution, expanding previous low-angular-momentum studies.

Findings

High angular momentum influences black hole growth and star formation.

Galactic rotation causes significant differences in galaxy evolution outcomes.

AGN feedback effects are qualitatively similar but quantitatively affected by angular momentum.

Abstract

This is the second paper of our series of works of studying the effects of active galactic nuclei (AGN) feedback on the cosmological evolution of an isolated elliptical galaxy by performing two-dimensional high-resolution hydrodynamical numerical simulations. In these simulations, the inner boundary is chosen so that the Bondi radius is resolved. Physical processes like star formation, SNe Ia and II are taken into account. Compared to previous works, the main improvements is that we adopt the most updated AGN physics, which is described in detail in the first paper of this series (Yuan et al. 2018, Paper I). These improvements include the discrimination of the two accretion modes of the central AGN and the most updated descriptions of the wind and radiation in the two modes. In Paper I, we consider the case that the specific angular momentum of the gas in the galaxy is very low. In this paper, we consider the case that the specific angular momentum of the gas is high. In the galactic scale, we adopt the gravitational torques raised due to non-axisymmetric structure in the galaxy as the mechanism of the transfer of angular momentum of gas, as proposed in some recent works. Since our simulations are axisymmetric, we make use of a parameterized prescription to mimic this mechanism. Same as Paper I, we investigate the AGN light curve, typical AGN lifetime, growth of the black hole mass, AGN duty-cycle, star formation, and the X-ray surface brightness of the galaxy. Special attention is paid to the effects of specific angular momentum of the galaxy on these properties. We find that some results are qualitatively similar to those shown in Paper I, while some results such as star formation and black hole growth do show a significant difference due to the mass concentration in the galactic disk as a consequence of galactic rotation.