Gamma-ray flux variability in the sample of EGRET blazars

Abstract

We analyze average gamma-ray variability statistics for the sample of blazars detected by CGRO/EGRET. We re-reduce all the available EGRET observations and analyze light curves by Monte Carlo modeling of the variability statistics including observational artifacts. We show that the observed variability behavior is dominated by the distribution of measurement errors which leads to strong systematical effects in all of the these statistics. General variability behavior detected by us is consistent with non-linear models and shows marginal correlation at long time scales in the structure function. We determine limits on distributions of the variability parameters with synthesis of flare population. We conclude that this method shows that all blazar light curves are consistent with a superposition of multiple flares.