Foschini, L.L.FoschiniDi Cocco, G.G.Di CoccoMalaguti, G.G.MalagutiGiommi, PaoloPaoloGiommi2020-09-172020-09-172005-05-01https://hdl.handle.net/20.500.13025/240The Astronomer's Telegram, #497The blazar 3C 454.3 (z = 0.859) has been observed by INTEGRAL as a Target-of-Opportunity for 200 ks, starting on May 15, 2005, at 18 40 UT following the announcement of a bright state at various frequencies (see Balonek, VSNET Alert; Remillard, ATel 484; Trushkin et al., ATel 488). The source was clearly detected by the IBIS/ISGRI instrument in the 20-40 and 40-100 keV energy bands, with a significance of 20 and 15 sigma, respectively.X-rayGamma RayRequest for ObservationsAGNQuasarsTransientsletterhttp://adsabs.harvard.edu/abs/2005ATel..497....1F2005ATel..497....1F