2006/02/15 by Elena Pian, E. Pian, L. Foschini +25 · 2 citations
Environmental Science · Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Insects and Parasite Interactions #Neutrino Physics Research #astro-ph
paper · pdf · doi:10.1051/0004-6361:200600017
5 pages, 3 eps figures, in press in A&A Letters
arxiv created 2006/02/15 · openalex publication_date 2006/03/21 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
In Spring 2005, the blazar 3C 454.3 underwent a dramatic outburst at all wavelengths from mm to X-rays. This prompted INTEGRAL observations, accomplished in 15-18 May 2005. The source was detected by the INTEGRAL instruments from 3 to 200 keV in a bright state ( erg s-1 cm-2), at least a factor of 2-3 higher than previously observed. This is one of the brightest blazar detections achieved by INTEGRAL. During the 2.5 days of INTEGRAL monitoring, we detected a ~20% decrease in the hard X-rays (20-40 keV), indicating that we have sampled the decaying part of the flare. The decrease is less apparent in the soft X-rays (5-15 keV). The simultaneous optical variations are weakly correlated with those at soft X-rays, and not clearly correlated with those at hard X-rays. The spectral energy distribution exhibits two components, as typically seen in blazars, which can be modeled with synchrotron radiation and inverse Compton scattering occurring in a region external to the broad line region.