The Radio to Gamma Ray Connection of EGRET Blazars: Correlation, Regression and Monte Carlo Analysis

TL;DR

This study analyzes the broadband properties of EGRET blazars, revealing correlations between gamma-ray and radio luminosities, and supports a synchrotron self-Compton model through Monte Carlo simulations, with implications for future gamma-ray observations.

Contribution

It provides the first comprehensive statistical analysis of EGRET blazars, demonstrating the relationship between gamma-ray and radio luminosities and supporting a specific emission model.

Findings

Gamma-ray luminosity scales with radio luminosity as L_gamma ∝ L_r^{0.77}

Monte Carlo simulations favor the synchrotron self-Compton model over external Compton scattering

Intrinsic radio luminosity ranges from 10^{21} to 10^{30} Watts Hz^{-1}

Abstract

A comprehensive statistical analysis of the broadband properties of EGRET blazars is presented. This analysis includes sources identified as blazars in the Sowards-Emmerd publications. Using this sample of 122 sources, we find that there is a relationship $L_\gamma \propto {L_r}^{0.77 \pm 0.03} $ as well as a correlation between $\alpha_{og}$ and $\alpha_{ro}$, and a correlation between radio luminosity and $\alpha_{og}$. Through the use of Monte Carlo simulations, we can replicate the observed luminosity relationship if a synchrotron self-Compton model is assumed. However, this relationship can not be replicated if an external Compton scattering model is assumed. These differences are primarily due to beaming effects. In addition it has been determined that the intrinsic radio luminosity of the parent sample falls in the range $10^{21} < L < 10^{30} {\rm Watts Hz^{-1}}$ and that the bulk Lorentz factors of the source are in the range $ 1 < \Gamma < 30 $, in a agreement with VLBI observations. Finally, we discuss implications for GLAST, successfully launched in June 2008.