AGILE gamma-ray detection of a strongly variable source in the Cygnus region

The AGILE satellite, currently in its Science Verification Phase, during the Observing Block that started on 2007-11-02 12 00 UT, detected significant and strongly variable gamma-ray emission from the Cygnus region lasting only about 1 day. The variable source positional error box is centered at Galactic coordinates l = 75.0 deg, b = -0.4 deg, and has a radius of about 1 degree. A preliminary maximum likelihood analysis of the AGILE-GRID (Gamma-Ray Imaging Detector) data obtained between 2007-11-23 03 58 55 and 2007-11-24 03 58 55 for photon energies above 100 MeV results in a detection significance of over 5 sigma.