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AGILE detects intense and prolonged gamma-ray activity from the FSRQ 3C 454.3

ATel #2322; E. Striani (Univ. Roma Tor Vergata and INFN Roma), S. Vercellone (INAF/IASF-Pa), F. Verrecchia, C. Pittori, P. Santolamazza (ASDC), M. Tavani (INAF/IASF-Rm), F. D'Ammando (Univ. Roma Tor Vergata and INAF/IASF-Rm), I. Donnarumma, V. Vittorini, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda, A. Argan, G. Piano, G. Pucella, S. Sabatini, A. Trois (INAF/IASF-Rm), A. Bulgarelli, F. Gianotti, M. Trifoglio, F. Fuschino, M. Galli, C. Labanti, M. Marisaldi, G. Di Cocco (INAF/IASF-Bo), A. Chen, A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Pellizzoni, M. Pilia (INAF/OA-Cagliari), G. Barbiellini, F. Longo, E. Moretti, E. Vallazza (INFN Trieste), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), S. Colafrancesco, P. Giommi,(ASDC), L. Salotti (ASI)
on 2 Dec 2009; 16:36 UT
Distributed as an Instant Email Notice Request For Observations
Credential Certification: Stefano Vercellone (stefano@iasf-milano.inaf.it)

Subjects: Gamma Ray, >GeV, Request for Observations, AGN, Quasar

Referred to by ATel #: 2325, 2326, 2328, 2329, 2332, 2333, 2345, 2352

The AGILE Gamma-Ray Imaging Detector (GRID) has been detecting prolonged flaring gamma-ray emission above 100 MeV from the flat spectrum radio quasar 3C 454.3.

Integrating from 2009-11-26 01:00UT to 2009-12-02 08:30UT, a quick-look maximum likelihood analysis yields a source flux of about 700e-8 ph/cm2/sec (E > 100 MeV), with a peak in the last 48 hours of the order of 1000e-8 ph/cm2/sec (E > 100 MeV).

This source behavior is different from what previously reported both by AGILE on a 2-year time-span (ATel #1160; ATel #1167; ATel #1278; ATel #1300; ATel #1545; ATel #1581; ATel #1592; ATel #1628; see also Vercellone et al., 2008, ApJL, 676, 13; Vercellone et al., 2009, ApJ, 690, 1018; Donnarumma et al., 2009, ApJ, in press [ArXiv:0910.4883]), and by Fermi during its first year (ATel #1628; ATel #2200). It is similar to what reported in (Abdo et al., 2009, ApJ, 699, 817) when the source exhibited a flare at a flux level of about 1200e-8 ph/cm2/sec (E > 100 MeV), and its flux remained above 700e-8 ph/cm2/sec (E > 100 MeV) for about 1 week.

The AGILE/GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. Multifrequency observations of the source are encouraged.