AGILE, Fermi, Swift, and GASP/WEBT multi-wavelength observations of the high-redshift blazar 4C +71.07 in outburst
Lähteenmäki, A.; Longo, F.; Morselli, A.; Colafrancesco, S.; Giroletti, M.; Villata, M.; Carnerero, M. I.; Raiteri, C. M.; Righini, S.; Romano, P.; Damljanovic, G.; Larionov, V. M.; Acosta-Pulido, J. A.; Arkharov, A. A.; Bachev, R.; Borman, G. A.; Di Paola, A.; Ehgamberdiev, Sh. A.; Grishina, T. S.; Klimanov, S. A.; Kopatskaya, E. N.; Kurtanidze, O. M.; Larionova, L. V.; Mihov, B.; Mirzaqulov, D. O.; Morozova, D. A.; Nazarov, S. V.; Savchenko, S. S.; Semkov, E.; Slavcheva-Mihova, L.; Strigachev, A.; Tornikoski, M.; Troitskaya, Yu. V.; Vince, O.; D'Ammando, F.; Orienti, M.; Agudo, I.; Donnarumma, I.; Vercellone, S.; Efimova, N. V.; Verrecchia, F.; Vittorini, V.; Tavani, M.; Bulgarelli, A.; Cattaneo, P. W.; Piano, G.; Pittori, C.; Lucarelli, F.; Munar-Adrover, P.; Parmiggiani, N.; Paoletti, F.; Bach, U.; Gómez, J. L.; Järvelä, E.; Casadio, C.; Molina, S. N.; Fioretti, V.; Doroshenko, V. T.; Butuzova, M. S.
Italy, Spain, Russia, Germany, Bulgaria, Serbia, Uzbekistan, Finland, Georgia, China, South Africa, United States
Abstract
Context. The flat-spectrum radio quasar 4C +71.07 is a high-redshift (z = 2.172), γ-loud blazar whose optical emission is dominated by thermal radiation from the accretion disc.
Aims: 4C +71.07 has been detected in outburst twice by the AGILE γ-ray satellite during the period from the end of October to mid-November 2015, when it reached a γ-ray flux of the order of F(E > 100 MeV)=(1.2 ± 0.3)×10-6 photons cm-2 s-1 and F(E > 100 MeV)=(3.1 ± 0.6)×10-6 photons cm-2 s-1, respectively, allowing us to investigate the properties of the jet and the emission region.
Methods: We investigated its spectral energy distribution by means of almost-simultaneous observations covering the cm, mm, near-infrared, optical, ultraviolet, X-ray, and γ-ray energy bands obtained by the GASP-WEBT Consortium and the Swift, AGILE, and Fermi satellites.
Results: The spectral energy distribution of the second γ-ray flare (whose energy coverage is more dense) can be modelled by means of a one-zone leptonic model, yielding a total jet power of about 4 × 1047 erg s-1.
Conclusions: During the most prominent γ-ray flaring period our model is consistent with a dissipation region within the broad-line region. Moreover, this class of high-redshift, flat-spectrum radio quasars with high-mass black holes might be good targets for future γ-ray satellites such as e-ASTROGAM.