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

AGILE pointed observations performed from July 9, 2007 to October 30, 2009 cover a very large time interval, with a gamma-ray data archive useful to perform monitoring studies of medium to high brightness gamma-ray sources in the 30 MeV-50 GeV energy range. The first AGILE Gamma-Ray Imaging Detector (GRID) catalog (Pittori et al., 2009) included a significance-limited (4sigma) sample of 47 sources (1AGL), detected with a conservative analysis over the first-year of operations.We present a variability study of the 1AGL sources over the complete AGILE pointed Observation Blocks (OBs) 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) dataset, integrating data on the OB timescales, mostly ranging between 4 and 30 days. The data processing resulted in an improved source list as compared to the 1AGL one. We present here our results on the variability of some of these sources.