A variability study of the AGILE first catalog of \gamma-ray sources on 2.3 years of AGILE pointed observations

TL;DR

This study analyzes 2.3 years of AGILE gamma-ray observations to update the catalog of galactic sources, focusing on variability and improved detection in complex regions of the galactic plane.

Contribution

It provides an improved and expanded catalog of gamma-ray sources using an enhanced data analysis method over a longer observation period.

Findings

Updated source list with more detections.

Identification of variability in some sources.

Enhanced detection in complex galactic regions.

Abstract

AGILE pointed observations performed from July 9, 2007 to October 30, 2009 cover a very large time interval, with a \gamma-ray dataset useful to perform studies of medium to high brightness galactic sources in the 30 MeV -- 50 GeV energy range. We present a study of the 1AGL galactic sources in the E > 100 MeV band, over the complete Agile pointed Observation Blocks (OBs) archive. The first AGILE Gamma-Ray Imaging Detector (GRID) catalog included a sample of 47 sources (1AGL; Pittori et al. 2009), detected with a conservative analysis over the first year of operations dataset. In the analysis here reported we used data obtained with an improved full Field of View (FOV) event filter, on a much larger (about 27.5 months) observation dataset, analyzing the merging of all data and each OB separately. The data processing resulted in an improved source list as compared to the 1AGL one, particularly in complex regions of the galactic plane. We present here some results on the revised 1AGL galactic sources and on the variability of some of them.