A Parameter Space Exploration of High Resolution Numerically Evolved Early Type Galaxies Including AGN Feedback and Accurate Dynamical Treatment of Stellar Orbits

TL;DR

This study uses high-resolution hydrodynamical simulations to explore how various parameters influence the evolution and observable properties of early-type galaxies with central supermassive black holes, including effects of AGN feedback and cosmological accretion.

Contribution

It provides a comprehensive parameter space exploration of ETGs, incorporating detailed physics like AGN feedback, star formation, and cosmological accretion, with results aligning well with observed galaxy properties.

Findings

Hot gas mass is about 10% of old stars' mass.

Cold gas disks are approximately 1 kpc in size.

New stars are concentrated in 0.1 kpc disks.

Abstract

An extensive exploration of the model parameter space of axisymmetric Early-Type Galaxies (ETGs) hosting a central supermassive Black Hole (SMBH) is conducted by means of high resolution hydrodynamical simulations performed with our code MACER. Global properties such as 1) total SMBH accreted mass, 2) final X-ray luminosity and temperature of the X-ray emitting halos, 3) total amount of new stars formed from the cooling gas, 4) total ejected mass in form of supernovae and AGN feedback induced galactic winds, are obtained as a function of galaxy structure and internal dynamics. In addition to the galactic dark matter halo, the model galaxies are also embedded in a group/cluster dark matter halo; finally cosmological accretion is also included, with amount and time dependence derived from cosmological simulations. Angular momentum conservation leads to the formation of cold HI disks; these disks further evolve under the action of star formation induced by disk instabilities, of the associated mass discharge onto the central SMBH, and of the consequent AGN feedback. At the end of the simulations, the hot (metal enriched) gas mass is roughly $10\%$ the mass in the old stars, with twice as much having been ejected into the intergalactic medium. The cold gas disks are a $\approx$ kpc in size, and the metal rich new stars are in $0.1$ kpc disks. The masses of cold gas and new stars are roughly $0.1\%$ the mass of the old stars. Overall, the final systems appear to reproduce quite successfully the main global properties of real ETGs.