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Title: High-redshift Blazars through NuSTAR eyes

The most powerful sources among the blazar family are MeV blazars. Often detected at z > 2, they usually display high X- and γ-ray luminosities, larger-than-average jet powers, and black hole masses ≳10 9 M . In the present work, we perform a multiwavelength study of three high-redshift blazars: 3FGL J0325.5+2223 (z = 2.06), 3FGL J0449.0+1121 (z = 2.15), and 3FGL J0453.2–2808 (z = 2.56), analyzing quasi-simultaneous data from GROND, Swift-UVOT and XRT, Nuclear Spectroscopic Telescope Array (NuSTAR), and Fermi-LAT. Our main focus is on the hard X-ray band recently unveiled by NuSTAR (3–79 keV) where these objects show a hard spectrum that enables us to constrain the inverse Compton (IC) peak and the jet power. We found that all three targets resemble the most powerful blazars, with the synchrotron peak located in the submillimeter range and the IC peak in the MeV range, and therefore belong to the MeV blazar class. Using a simple one-zone leptonic emission model to reproduce the spectral energy distributions, we conclude that a simple combination of synchrotron and accretion disk emission reproduces the infrared–optical spectra, while the X-ray to γ-ray part is well reproduced by the IC scattering of low-energy photons supplied by themore » broad-line region. The black hole masses for each of the three sources are calculated to be ≳4 × 10 8 M . Finally, the three studied sources have jet power at the level of, or beyond, the accretion luminosity.« less
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  1. Clemson Univ., Clemson, SC (United States)
  2. Agenzia Spaziale Italiana (ASI) Science Data Center, Roma (Italy); Istituto Nazionale di Fisica Nucleare, Perugia (Italy)
  3. Max Planck Institute fur extraterrestrische Physik, Garching (Germany)
  4. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  5. SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 839; Journal Issue: 2; Journal ID: ISSN 1538-4357
Institute of Physics (IOP)
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; galaxies: active; galaxies: jets; gamma rays: galaxies; quasars: individual (3FGL J0325.5+2223, 3FGL J0449.0+1121, 3FGL J0453.2–2808)
OSTI Identifier: