A mixture evolution scenario of the AGN radio luminosity function

TL;DR

This paper introduces a mixture evolution model for the radio luminosity function of steep spectrum AGNs, combining density and luminosity evolution, and uses Bayesian methods to fit the model to observational data.

Contribution

It presents a novel mixture evolution scenario that explains the luminosity-dependent evolution of the AGN radio luminosity function using Bayesian modeling.

Findings

Density evolution is positive until z~0.9, then becomes negative.

Luminosity evolution remains positive up to z~3.5-5, then declines.

Modeled RLFs agree well with previous studies.

Abstract

We propose a mixture evolution scenario to model the evolution of the radio luminosity function (RLF) of steep spectrum AGNs (active galactic nuclei) based on a Bayesian method. In this scenario, the shape of the RLF is determined by both the density and luminosity evolution. Our models indicate that the density evolution is positive until a redshift of $\thicksim 0.9$, at which point it becomes negative, while the luminosity evolution is positive to a higher redshift ($z \thicksim 5$ for model B and $z \thicksim 3.5$ for model C), where it becomes negative. Our mixture evolution model works well, and the modeled RLFs are in good agreement with previous determinations. The mixture evolution scenario can naturally explain the luminosity-dependent evolution of the RLFs.