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Title: The highest redshift quasar at z = 7.085: A radio-quiet source

Abstract

We present 1-2 GHz Very Large Array A-configuration continuum observations on the highest redshift quasar known to date, the z = 7.085 quasar ULAS J112001.48+064124.3. The results show no radio continuum emission at the optical position of the quasar or its vicinity at a level of ≥3σ or 23.1 μJy beam{sup –1}. This 3σ limit corresponds to a rest-frame 1.4 GHz luminosity density limit of L {sub ν,} {sub 1.4} {sub GHz} < 1.76 × 10{sup 24} W Hz{sup –1} for a spectral index of α = 0, and L {sub ν,} {sub 1.4} {sub GHz} < 1.42 × 10{sup 25} W Hz{sup –1} for a spectral index of α = –1. The rest-frame 1.4 GHz luminosity limits are L {sub rad} < 6.43 × 10{sup 6} L {sub ☉} and L {sub rad} < 5.20 × 10{sup 7} L {sub ☉} for α = 0 and α = –1, respectively. The derived limits for the ratio of the rest-frame 1.4 GHz luminosity density to the B-band optical luminosity density are R{sub 1.4}{sup ∗}<0.53 and <4.30 for the above noted spectral indices, respectively. Given our upper limits on the radio continuum emission and the radio-to-optical luminosity ratio, we conclude thatmore » this quasar is radio-quiet and located at the low end of the radio-quiet distribution of high-redshift (z ≳ 6) quasars.« less

Authors:
;  [1];
  1. National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States)
Publication Date:
OSTI Identifier:
22340049
Resource Type:
Journal Article
Journal Name:
Astronomical Journal (New York, N.Y. Online)
Additional Journal Information:
Journal Volume: 147; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1538-3881
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BEAMS; CONFIGURATION; DENSITY; DISTRIBUTION; EMISSION; GALAXIES; GHZ RANGE; LUMINOSITY; QUASARS; RED SHIFT

Citation Formats

Momjian, E., Carilli, C. L., Walter, F., and Venemans, B., E-mail: emomjian@nrao.edu, E-mail: ccarilli@nrao.edu, E-mail: walter@mpia.de, E-mail: venemans@mpia.de. The highest redshift quasar at z = 7.085: A radio-quiet source. United States: N. p., 2014. Web. doi:10.1088/0004-6256/147/1/6.
Momjian, E., Carilli, C. L., Walter, F., & Venemans, B., E-mail: emomjian@nrao.edu, E-mail: ccarilli@nrao.edu, E-mail: walter@mpia.de, E-mail: venemans@mpia.de. The highest redshift quasar at z = 7.085: A radio-quiet source. United States. https://doi.org/10.1088/0004-6256/147/1/6
Momjian, E., Carilli, C. L., Walter, F., and Venemans, B., E-mail: emomjian@nrao.edu, E-mail: ccarilli@nrao.edu, E-mail: walter@mpia.de, E-mail: venemans@mpia.de. 2014. "The highest redshift quasar at z = 7.085: A radio-quiet source". United States. https://doi.org/10.1088/0004-6256/147/1/6.
@article{osti_22340049,
title = {The highest redshift quasar at z = 7.085: A radio-quiet source},
author = {Momjian, E. and Carilli, C. L. and Walter, F. and Venemans, B., E-mail: emomjian@nrao.edu, E-mail: ccarilli@nrao.edu, E-mail: walter@mpia.de, E-mail: venemans@mpia.de},
abstractNote = {We present 1-2 GHz Very Large Array A-configuration continuum observations on the highest redshift quasar known to date, the z = 7.085 quasar ULAS J112001.48+064124.3. The results show no radio continuum emission at the optical position of the quasar or its vicinity at a level of ≥3σ or 23.1 μJy beam{sup –1}. This 3σ limit corresponds to a rest-frame 1.4 GHz luminosity density limit of L {sub ν,} {sub 1.4} {sub GHz} < 1.76 × 10{sup 24} W Hz{sup –1} for a spectral index of α = 0, and L {sub ν,} {sub 1.4} {sub GHz} < 1.42 × 10{sup 25} W Hz{sup –1} for a spectral index of α = –1. The rest-frame 1.4 GHz luminosity limits are L {sub rad} < 6.43 × 10{sup 6} L {sub ☉} and L {sub rad} < 5.20 × 10{sup 7} L {sub ☉} for α = 0 and α = –1, respectively. The derived limits for the ratio of the rest-frame 1.4 GHz luminosity density to the B-band optical luminosity density are R{sub 1.4}{sup ∗}<0.53 and <4.30 for the above noted spectral indices, respectively. Given our upper limits on the radio continuum emission and the radio-to-optical luminosity ratio, we conclude that this quasar is radio-quiet and located at the low end of the radio-quiet distribution of high-redshift (z ≳ 6) quasars.},
doi = {10.1088/0004-6256/147/1/6},
url = {https://www.osti.gov/biblio/22340049}, journal = {Astronomical Journal (New York, N.Y. Online)},
issn = {1538-3881},
number = 1,
volume = 147,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 2014},
month = {Wed Jan 01 00:00:00 EST 2014}
}