Characteristics of Powerful Radio Galaxies

TL;DR

This paper explores the evolution of powerful radio galaxies, linking their unique features to the time evolution of radio quasars and proposing a model where tilted accretion disks influence their characteristics.

Contribution

It introduces a new model predicting tilted accretion disks in bright quasars, explaining the distinctive features of mature radio galaxies as a result of their evolutionary stage.

Findings

Distinctive characteristics of mature radio galaxies are linked to their evolution from radio quasars.

Tilted accretion disks are predicted to occur in bright quasars but not in other AGN subclasses.

Counter-rotation plays a key role in black hole feedback mechanisms.

Abstract

Mature radio galaxies such as M87 belong to a specific subclass of active galaxies (AGN) whose evolution in time endows them with five distinguishing characteristics, including (1) low excitation emission, (2) low star formation rates, (3) high bulge stellar-velocity dispersion, (4) bright stellar nuclei, and (5) weak or nonexistent merger signatures. We show how to understand these seemingly disparate characteristics as originating from the time evolution of powerful radio quasars and describe a new model prediction that tilted accretion disks in AGN are expected to occur in bright quasars but not in other subclasses of AGN. The picture we present should be understood as the most compelling evidence for counter-rotation as a key element in feedback from accreting black holes.