GASP detection of a fast optical brightening of the blazar 3C 454.3
M. Villata  and C. M. Raiteri (INAF, Osservatorio  Astronomico di Torino, Italy), V. M. Larionov and T. S. Konstantinova (Astronomical Institute, St.-Petersburg State University, Russia), K. Nilsson and M. Pasanen (Tuorla Observatory, University of Turku, Finland), D. Carosati (EPT Observatories, Tijarafe, La Palma, Spain), for the GASP Collaboration
With reference to the recent very strong gamma-ray activity of the blazar 3C 454.3 detected by Fermi-GST and AGILE (ATel #2322), the GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT) reports on a simultaneous fast optical brightening of the source. After the mild activity registered in August-October 2009 (R ~ 14.5-15), the optical brightness decreased to R ~ 15-15.2 in November. Starting from this level, a very fast flux increase has led to a brightening of more than 1 mag between November 21 and December 1-2, when reaching R ~ 14.1.
optical,gamma ray,agn,blazar