Dynamical processes in galaxy centers

TL;DR

This paper reviews the complex, chaotic processes that drive gas inflow and outflow in galaxy centers, highlighting the roles of instabilities, interactions, and the variability across different scales.

Contribution

It synthesizes observational and simulation data to elucidate the mechanisms and efficiency of gas fueling and feedback in galaxy nuclei.

Findings

Gas inflow is chaotic and intermittent.

Non-axisymmetries are driven by instabilities and interactions.

Fueling processes vary across galaxy scales.

Abstract

How does the gas get in nuclear regions to fuel black holes? How efficient is the feedback? The different processes to cause rapid gas inflow (or outflow) in galaxy centers are reviewed. Non axisymmetries can be created or maintained by internal disk instabilities, or galaxy interactions. Simulations and observations tell us that the fueling is a chaotic and intermittent process, with different scenarios and time-scales, according to the various radial scales across a galaxy.