Ionized outflows from active galactic nuclei as the essential elements of feedback

TL;DR

This review discusses the physics, observations, and mechanisms of ionized outflows from active galactic nuclei, emphasizing their role in galaxy feedback and future prospects with advanced telescopes and simulations.

Contribution

It provides a comprehensive summary of current knowledge, uncertainties, and future directions in understanding AGN ionized outflows and their impact on galaxy evolution.

Findings

Ionized outflows are detected in over 50% of nearby AGN.

These outflows carry significant kinetic energy, affecting host galaxy evolution.

Advancements in high-resolution spectroscopy and simulations will enhance understanding in the next decade.

Abstract

Outflows from active galactic nuclei (AGN) are one of the fundamental mechanisms by which the central supermassive black hole interacts with its host galaxy. Detected in $\ge 50\%$ of nearby AGN, these outflows have been found to carry kinetic energy that is a significant fraction of AGN power, and thereby give negative feedback to their host galaxies. To understand the physical processes that regulate them, it is important to have a robust estimate of their physical and dynamical parameters. In this review we summarize our current understanding on the physics of the ionized outflows detected in absorption in the UV and X-ray wavelength bands. We discuss the most relevant observations and our current knowledge and uncertainties in the measurements of the outflow parameters. We also discuss their origin and acceleration mechanisms. The commissioning and concept studies of large telescope missions with high resolution spectrographs in UV/optical and X-rays along with rapid advancements in simulations offer great promise for discoveries in this field over the next decade.