The Bright $\gamma$-ray Flare of 3C 279 in June 2015: AGILE Detection and Multifrequency Follow-up Observations

C. Pittori; F. Lucarelli; F. Verrecchia; C. M. Raiteri; M. Villata; V. Vittorini; M. Tavani; S. Puccetti; M. Perri; I. Donnarumma; S. Vercellone; J. A. Acosta-Pulido; R. Bachev; E. Benitez; G. A. Borman; M. I. Carnerero; D. Carosati; W. P. Chen; Sh. A. Ehgamberdiev; A. Goded; T. S. Grishina; D. Hiriart; H. Y. Hsiao; S. G. Jorstad; G. N. Kimeridze; E. N. Kopatskaya; O. M. Kurtanidze; S. O. Kurtanidze; V. M. Larionov; L. V. Larionova; A. P. Marscher; D. O. Mirzaqulov; D. A. Morozova; K. Nilsson; M. R. Samal; L. A. Sigua; B. Spassov; A. Strigachev; L. O. Takalo; L. A. Antonelli; A. Bulgarelli; P. Cattaneo; S. Colafrancesco; P. Giommi; F. Longo; A. Morselli; F. Paoletti

doi:10.3847/1538-4357/aab1f9

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arXiv · 1803.07529

The Bright $\gamma$-ray Flare of 3C 279 in June 2015: AGILE Detection and Multifrequency Follow-up Observations

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Abstract

We report the AGILE detection and the results of the multifrequency follow-up observations of a bright $\gamma$-ray flare of the blazar 3C 279 in June 2015. We use AGILE-GRID and Fermi-LAT $\gamma$-ray data, together with Swift-XRT, Swift-UVOT, and ground-based GASP-WEBT optical observations, including polarization information, to study the source variability and the overall spectral energy distribution during the $\gamma$-ray flare. The $\gamma$-ray flaring data, compared with as yet unpublished simultaneous optical data which allow to set constraints on the big blue bump disk luminosity, show very high Compton dominance values of $\sim 100$, with a ratio of $\gamma$-ray to optical emission rising by a factor of three in a few hours. The multi-wavelength behavior of the source during the flare challenges one-zone leptonic theoretical models. The new observations during the June 2015 flare are also compared with already published data and non-simultaneous historical 3C 279 archival data.

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C. Pittori, F. Lucarelli, F. Verrecchia, C. M. Raiteri, M. Villata, V. Vittorini, M. Tavani, S. Puccetti, M. Perri, I. Donnarumma, S. Vercellone, J. A. Acosta-Pulido, R. Bachev, E. Benitez, G. A. Borman, M. I. Carnerero, D. Carosati, W. P. Chen, Sh. A. Ehgamberdiev, A. Goded, T. S. Grishina, D. Hiriart, H. Y. Hsiao, S. G. Jorstad, G. N. Kimeridze, E. N. Kopatskaya, O. M. Kurtanidze, S. O. Kurtanidze, V. M. Larionov, L. V. Larionova, A. P. Marscher, D. O. Mirzaqulov, D. A. Morozova, K. Nilsson, M. R. Samal, L. A. Sigua, B. Spassov, A. Strigachev, L. O. Takalo, L. A. Antonelli, A. Bulgarelli, P. Cattaneo, S. Colafrancesco, P. Giommi, F. Longo, A. Morselli, F. Paoletti. 2018-03-20. The Bright $\gamma$-ray Flare of 3C 279 in June 2015: AGILE Detection and Multifrequency Follow-up Observations. https://doi.org/10.3847/1538-4357/aab1f9

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