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A luminous quasar at a redshift of z = 7.085

Open access
Mortlock, Daniel J., Warren, Stephen J., Venemans, Bram P., Patel, Mitesh, Hewett, Paul C., McMahon, Richard G., Simpson, Chris, Theuns, Tom, Gonzáles-Solares, Eduardo A., Adamson, Andy, Dye, Simon, Hambly, Nigel C., Hirst, Paul, Irwin, Mike J., Kuiper, Ernst, Lawrence, Andy, Röttgering, Huub J. A.·2011·Nature

Abstract

The intergalactic medium was not completely reionized until approximately a billion years after the Big Bang, as revealed by observations of quasars with redshifts of less than 6.5. It has been difficult to probe to higher redshifts, however, because quasars have historically been identified in optical surveys, which are insensitive to sources at redshifts exceeding 6.5. Here we report observations of a quasar (ULAS J112001.48+064124.3) at a redshift of 7.085, which is 0.77 billion years after the Big Bang. ULAS J1120+0641 has a luminosity of 6.3 × 1013L⊙ and hosts a black hole with a mass of 2 × 109M⊙ (where L⊙ and M⊙ are the luminosity and mass of the Sun). The measured radius of the ionized near zone around ULAS J1120+0641 is 1.9 megaparsecs, a factor of three smaller than is typical for quasars at redshifts between 6.0 and 6.4. The near-zone transmission profile is consistent with a Lyα damping wing, suggesting that the neutral fraction of the intergalactic medium in front of ULAS J1120+0641 exceeded 0.1.

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Metadata

Authors
Mortlock, D. J., Warren, S. J., Venemans, B. P., Patel, M., Hewett, P. C., McMahon, R. G., Simpson, C., Theuns, T., Gonzáles-Solares, E. A., Adamson, A., Dye, S., Hambly, N. C., Hirst, P., Irwin, M. J., Kuiper, E., Lawrence, A., & Röttgering, H. J. A.
Venue
Nature
Published
2011-06
Volume
474
Issue
7353
Pages
616-619
ISSN
  • 0028-0836 (ISSN-L)
  • 1476-4687
OpenAlex
W1975627161
Cited by
1,494
References
1
FWCI
54.10
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: A luminous quasar at a redshift of z = 7.085. https://app.cochat.ai/papers/10.1038/nature10159
The paper
Mortlock, D. J., Warren, S. J., Venemans, B. P., Patel, M., Hewett, P. C., McMahon, R. G., Simpson, C., Theuns, T., Gonzáles-Solares, E. A., Adamson, A., Dye, S., Hambly, N. C., Hirst, P., Irwin, M. J., Kuiper, E., Lawrence, A., & Röttgering, H. J. A. (2011). A luminous quasar at a redshift of z = 7.085. Nature. https://doi.org/10.1038/nature10159

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

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