Fermi Gamma-ray Space Telescope Observations of the Gamma-ray Outburst from 3C454.3 in November 2010

The flat-spectrum radio quasar 3C454.3 underwent an extraordinary 5-day γ-ray outburst in November 2010 when the daily flux measured with the Fermi Large Area Telescope (LAT) at photon energies E > 100MeV reached (66±2) × 10^-6ph cm^-2s^-1. This is a factor of 3 higher than its previous maximum flux recorded in December 2009 and > 5 times brighter than the Vela pulsar, which is normally the brightest source in the γ-ray sky. The 3-hr peak flux was (85±5)×10^-6ph cm^-2s^-1, corresponding to an apparent isotropic luminosity of (2.1±0.2)×10⁵⁰ erg s^-1, the highest ever recorded for a blazar. In this talk, we investigate the features of this exceptional event in the γ-ray band of the Fermi-LAT.