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Emission-Line Properties of z ≥ 4 QSOs

Published online by Cambridge University Press:  12 April 2016

J.C. Shields
Affiliation:
Steward Observatory, University of Arizona, Tucson, AZ 85721, USA
F. Hamann
Affiliation:
Center for Astrophysics and Space Sciences, University of California at San Diego, La Jolla, CA 92093, USA
C.B. Foltz
Affiliation:
MMT Observatory, University of Arizona, Tucson, AZ 85721, USA
F.H. Chaffee
Affiliation:
MMT Observatory, University of Arizona, Tucson, AZ 85721, USA

Abstract

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We report on preliminary results of a program of rest-frame UV spectroscopy of z ≥ 4 QSOs. Despite their high luminosity and inherent youth, these objects exhibit spectra that are generally very similar to those of AGNs at lower z. We find some evidence that the z ≥ 4 systems are described by unusually strong O Iλ1304 emission, which may be a result of elevated metallicity or unusual prominence of the ‘intermediate-line region’. High metallicities are also signaled by strong N Vλ1240 emission, consistent with quasar behavior at z ≈ 2–3.

Type
II. Broad Emission Lines
Copyright
Copyright © Astronomical Society of the Pacific 1997

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