Gamma-ray luminosity function of Gamma-ray bright AGNs

TL;DR

This paper analyzes the gamma-ray luminosity functions of blazars, specifically FSRQs and BL Lacs, revealing different evolutionary behaviors and constraining their luminosity distributions using observational data from the CGRO.

Contribution

It provides the first separate analysis of FSRQ and BL Lac gamma-ray luminosity functions, highlighting their distinct evolutionary patterns and constraining their luminosity distribution parameters.

Findings

BL Lacs show no evolution in gamma-ray luminosity.

FSRQs exhibit significant luminosity evolution.

Luminosity function for BL Lacs shows no break.

Abstract

Detection of Gamma-ray emission from a class of active galactic nuclei (viz blazars), has been one of the important findings from the Compton Gamma Ray Observatory (CGRO). However, their Gamma-ray luminosity function has not been well determined. Few attempts have been made in earlier works, where BL Lacs and Flat Spectrum Radio Quasars (FSRQs) have been considered as a single source class. In this paper we investigated the evolution and Gamma-ray luminosity function of FSRQs and BL Lacs separately. Our investigation indicates no evolution for BL Lacs, however FSRQs show significant evolution. Pure luminosity evolution is assumed for FSRQs and exponential and power law evolution models are examined. Due to the small number of sources, the low luminosity end index of the luminosity function for FSRQs is constrained with upper limit. BL Lac luminosity function shows no signature of break. As a consistency check, the model source distributions deriving from these luminosity functions show no significant departure from the observed source distributions.