AGN feedback and star formation in ETGs: negative and positive feedback

TL;DR

This paper uses advanced simulations to explore how AGN feedback in early type galaxies can both suppress and trigger star formation, revealing complex, structured interactions.

Contribution

It introduces high-resolution 2D hydrodynamical simulations with radiative transport to study the dual role of AGN feedback in star formation regulation.

Findings

AGN feedback suppresses recurrent cooling flows.

AGN feedback induces star formation in galaxy centers.

Feedback effects are highly structured spatially and temporally.

Abstract

AGN feedback from supermassive black holes (SMBHs) at the center of early type galaxies is commonly invoked as the explanation for the quenching of star formation in these systems. The situation is complicated by the significant amount of mass injected in the galaxy by the evolving stellar population over cosmological times. In absence of feedback, this mass would lead to unobserved galactic cooling flows, and to SMBHs two orders of magnitude more massive than observed. By using high-resolution 2D hydrodynamical simulations with radiative transport and star formation in state-of-the-art galaxy models, we show how the intermittent AGN feedback is highly structured on spatial and temporal scales, and how its effects are not only negative (shutting down the recurrent cooling episodes of the ISM), but also positive, inducing star formation in the inner regions of the host galaxy.