摘要：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 AGILEγ-ray satellite during the period from the end of October to mid-November 2015, when it reached aγ-ray flux of the order ofF(E > 100 MeV)=(1.2 ± 0.3)×10−6photons cm−2s−1andF(E > 100 MeV)=(3.1 ± 0.6)×10−6photons cm−2s−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, andγ-ray energy bands obtained by the GASP-WEBT Consortium and theSwift, AGILE, andFermisatellites.Results.The spectral energy distribution of the secondγ-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 × 1047erg s−1.Conclusions.During the most prominentγ-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 futureγ-ray satellites such as e-ASTROGAM.
关键词：enacceleration of particlesradiation mechanisms: non-thermalrelativistic processesquasars: supermassive black holesquasars: individual: 4C +71.07gamma rays: galaxies
