AGILE observations of intense gamma-ray emission from the blazar 3C 279

ATel #11200; F. Lucarelli (SSDC and INAF/OAR), A. Bulgarelli (INAF/IASF-Bo), F. Verrecchia, C. Pittori (SSDC and INAF/OAR), N. Parmiggiani (INAF/IASF-Bo), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo, G. Piano, A. Ursi (INAF/IAPS), S. Vercellone (INAF/OA-Brera), M. Pilia (INAF/OA-Cagliari), I. Donnarumma (ASI), V. Fioretti, F. Gianotti, M. Trifoglio (INAF/IASF-Bo), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Chen (Wits University), A. Argan, E. Costa, E. Del Monte, Y. Evangelista, M. Feroci, F. Lazzarotto, I. Lapshov, L. Pacciani, P. Soffitta, S. Sabatini, V. Vittorini (INAF/IAPS), G. Pucella, M. Rapisarda (ENEA-Frascati), G. Di Cocco, F. Fuschino, M. Galli, C. Labanti, M. Marisaldi (INAF/IASF-Bo), A. Pellizzoni, A. Trois (INAF/OA-Cagliari), G. Barbiellini, E. Vallazza (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), S. Colafrancesco (INAF/OAR and Wits University), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), A. Ferrari (Univ. Torino and CIFS), F. Paoletti (East Windsor RSD Hightstown and INAF/IAPS), A. Antonelli (SSDC), P. Giommi, L. Salotti, G. Valentini, and F. D'Amico (ASI)
on 19 Jan 2018; 14:45 UT
Credential Certification: Fabrizio Lucarelli (fabrizio.lucarelli@asdc.asi.it)

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AGILE is detecting an intense gamma-ray emission above 100 MeV from a source consistent with the Flat Spectrum Radio Quasar 3C 279 (RA: 194.046527 deg, Dec: -5.789312 deg, J2000) at z=0.536.

Integrating from 2018-01-18 03:50 UT to 2018-01-19 03:50 UT, a maximum likelihood analysis yields a detection at a significance level above 12 sigma, and a flux F = (1.8 +/- 0.3) x 10^-5 ph/cm^2/s (E > 100 MeV). For a 12-hour integration, starting from 2018-01-18 00:00 UT, a preliminary maximum likelihood analysis yields a flux F = (2.2 +/- 0.5) x 10^-5 ph/cm^2/s (E > 100 MeV).

This is the highest flux above 100 MeV measured by AGILE since June 2015 (ATel #7631, #7633, Pittori et al. 2018 (submitted to ApJ)), and higher with respect to the recent detections reported by Fermi-LAT in ATel #11189 and by AGILE in ATel #11115. The source is also reported to be in optical high-state (ATel #11190, #11196).

The AGILE-GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. The source can be monitored with the public mobile application "AGILEScience" developed by the AGILE Team, available for both Android and iOS devices.

Multifrequency observations of 3C 279 are strongly encouraged.