Gamma-ray blazars within the first 2 billion years

Journal Article · Wed Mar 01 04:00:00 UTC 2017 · Astrophysical Journal Letters

DOI:https://doi.org/10.3847/2041-8213/AA5FFF· OSTI ID:22869300

Ackermann, M.; Buehler, R. ^[1]; Ajello, M. ^[2]; Baldini, L. ^[3]; Ballet, J. ^[4]; Barbiellini, G. ^[5]; Bastieri, D. ^[6]; Gonzalez, J. Becerra; Buson, S. ^[7]; Bellazzini, R. ^[8]; Bissaldi, E.; Caragiulo, M. ^[9]; Blandford, R. D.; Bloom, E. D.; Bottacini, E.; Cameron, R. A. ^[10]; Bonino, R. ^[11]; Bregeon, J. ^[12]; Bruel, P. ^[13]; others, and

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1. Deutsches Elektronen Synchrotron DESY, D-15738 Zeuthen (Germany)
2. Department of Physics and Astronomy, Clemson University, Kinard Lab of Physics, Clemson, SC 29634-0978 (United States)
3. Università di Pisa and Istituto Nazionale di Fisica Nucleare, Sezione di Pisa I-56127 Pisa (Italy)
4. Laboratoire AIM, CEA-IRFU/CNRS/Université Paris Diderot, Service d’Astrophysique, CEA Saclay, F-91191 Gif sur Yvette (France)
5. Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy)
6. Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy)
7. NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
8. Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy)
9. Istituto Nazionale di Fisica Nucleare, Sezione di Bari, I-70126 Bari (Italy)
10. W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States)
11. Istituto Nazionale di Fisica Nucleare, Sezione di Torino, I-10125 Torino (Italy)
12. Laboratoire Univers et Particules de Montpellier, Université Montpellier, CNRS/IN2P3, F-34095 Montpellier (France)
13. Laboratoire Leprince-Ringuet, École polytechnique, CNRS/IN2P3, F-91128 Palaiseau (France)

The detection of high-redshift (z >3) blazars enables the study of the evolution of the most luminous relativistic jets over cosmic time. More importantly, high-redshift blazars tend to host massive black holes and can be used to constrain the space density of heavy black holes in the early universe. Here, we report the first detection with the Fermi-Large Area Telescope of five γ-ray-emitting blazars beyond z = 3.1, more distant than any blazars previously detected in γ-rays. Among these five objects, NVSS J151002+570243 is now the most distant known γ-ray-emitting blazar at z = 4.31. These objects have steeply falling γ-ray spectral energy distributions (SEDs), and those that have been observed in X-rays have a very hard X-ray spectrum, both typical of powerful blazars. Their Compton dominance (ratio of the inverse Compton to synchrotron peak luminosities) is also very large (>20). All of these properties place these objects among the most extreme members of the blazar population. Their optical spectra and the modeling of their optical-UV SEDs confirm that these objects harbor massive black holes (M{sub BH}∼10{sup 8−10} M{sub ⊙}). We find that, at z≈4, the space density of >10{sup 9} M{sub ⊙} black holes hosted in radio-loud and radio-quiet active galactic nuclei are similar, implying that radio-loudness may play a key role in rapid black hole growth in the early universe.

• OSTI ID: 22869300
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 837; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BLACK HOLES
COMPTON EFFECT
ENERGY SPECTRA
GALACTIC EVOLUTION
GALAXY NUCLEI
GAMMA RADIATION
HARD X RADIATION
JETS
LUMINOSITY
QUASARS
RED SHIFT
RELATIVISTIC RANGE
SYNCHROTRON RADIATION
TELESCOPES
UNIVERSE
X-RAY SPECTRA