2009/10/28 by S. Vercellone, Vercellone, S.
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #FOS: Physical sciences #Gamma-ray bursts and supernovae #High Energy Astrophysical Phenomena (astro-ph.HE) #Radio Astronomy Observations and Technology #astro-ph.HE
paper · pdf · doi:10.48550/arxiv.0910.5325
Invited Talk presented at the Conference "Accretion and Ejection in AGN: A Global View" (Como, June 22-26, 2009)
arxiv created 2009/10/28 · openalex publication_date 2009/10/28 · openalex created_date 2016/06/24 · arxiv updated 2019/08/14 · openalex updated_date 2026/07/28
During the period July 2007 - January 2009, the AGILE satellite, together with several other space- and ground-based observatories monitored the activity of the flat-spectrum radio quasar 3C 454.3, yielding the longest multiwavelength coverage of this gamma-ray quasar so far. The source underwent an unprecedented period of very high activity above 100 MeV, a few times reaching gamma-ray flux levels on a day time scale higher than F=400 x 10-8 ph cm-2 s-1, in conjunction with an extremely variable behavior in the optical R-band, even of the order of several tenth of magnitude in few hours, as shown by the GASP-WEBT light curves. We present the results of this long term multiwavelength monitoring campaign, with particular emphasis on the study of possible lags between the different wavebands, and the results of the modeling of simultaneous spectral energy distributions at different levels of activity.