The ultraviolet spectra of radio-loud and radio-quiet quasars

Paul J. Francis, Eric J. Hooper, Christopher D Impey

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

The rest-frame ultraviolet spectral properties of matched samples of radio-loud, radio-moderate, and radio-quiet quasars are investigated, using quasars drawn from the Large Bright QSO Survey. We confirm the absence of spectral differences between radio-loud and radio-quiet quasars at rest-frame wavelengths longward of 1600 Å, as reported by previous authors. However, at shorter wavelengths we find a significant difference: radio-loud quasars have narrower (96% confidence), higher equivalent width (97% confidence) Lyman-α and C IV emission lines. We further investigate quasars which are radio quiet, but have radio-to-optical flux ratios at the upper extreme of the radio-quiet population. Broad absorption line quasars are overabundant by a factor of ∼10 in this radio-moderate population; the overabundance is significant at a 99.99% confidence level.

Original languageEnglish (US)
Pages (from-to)417-425
Number of pages9
JournalAstronomical Journal
Volume106
Issue number2
StatePublished - Aug 1993

Fingerprint

ultraviolet spectra
quasars
radio
confidence
wavelengths
wavelength

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

The ultraviolet spectra of radio-loud and radio-quiet quasars. / Francis, Paul J.; Hooper, Eric J.; Impey, Christopher D.

In: Astronomical Journal, Vol. 106, No. 2, 08.1993, p. 417-425.

Research output: Contribution to journalArticle

Francis, PJ, Hooper, EJ & Impey, CD 1993, 'The ultraviolet spectra of radio-loud and radio-quiet quasars', Astronomical Journal, vol. 106, no. 2, pp. 417-425.
Francis, Paul J. ; Hooper, Eric J. ; Impey, Christopher D. / The ultraviolet spectra of radio-loud and radio-quiet quasars. In: Astronomical Journal. 1993 ; Vol. 106, No. 2. pp. 417-425.
@article{3743df6e6f694f3498ced2081b66580c,
title = "The ultraviolet spectra of radio-loud and radio-quiet quasars",
abstract = "The rest-frame ultraviolet spectral properties of matched samples of radio-loud, radio-moderate, and radio-quiet quasars are investigated, using quasars drawn from the Large Bright QSO Survey. We confirm the absence of spectral differences between radio-loud and radio-quiet quasars at rest-frame wavelengths longward of 1600 {\AA}, as reported by previous authors. However, at shorter wavelengths we find a significant difference: radio-loud quasars have narrower (96{\%} confidence), higher equivalent width (97{\%} confidence) Lyman-α and C IV emission lines. We further investigate quasars which are radio quiet, but have radio-to-optical flux ratios at the upper extreme of the radio-quiet population. Broad absorption line quasars are overabundant by a factor of ∼10 in this radio-moderate population; the overabundance is significant at a 99.99{\%} confidence level.",
author = "Francis, {Paul J.} and Hooper, {Eric J.} and Impey, {Christopher D}",
year = "1993",
month = "8",
language = "English (US)",
volume = "106",
pages = "417--425",
journal = "Astronomical Journal",
issn = "0004-6256",
publisher = "IOP Publishing Ltd.",
number = "2",

}

TY - JOUR

T1 - The ultraviolet spectra of radio-loud and radio-quiet quasars

AU - Francis, Paul J.

AU - Hooper, Eric J.

AU - Impey, Christopher D

PY - 1993/8

Y1 - 1993/8

N2 - The rest-frame ultraviolet spectral properties of matched samples of radio-loud, radio-moderate, and radio-quiet quasars are investigated, using quasars drawn from the Large Bright QSO Survey. We confirm the absence of spectral differences between radio-loud and radio-quiet quasars at rest-frame wavelengths longward of 1600 Å, as reported by previous authors. However, at shorter wavelengths we find a significant difference: radio-loud quasars have narrower (96% confidence), higher equivalent width (97% confidence) Lyman-α and C IV emission lines. We further investigate quasars which are radio quiet, but have radio-to-optical flux ratios at the upper extreme of the radio-quiet population. Broad absorption line quasars are overabundant by a factor of ∼10 in this radio-moderate population; the overabundance is significant at a 99.99% confidence level.

AB - The rest-frame ultraviolet spectral properties of matched samples of radio-loud, radio-moderate, and radio-quiet quasars are investigated, using quasars drawn from the Large Bright QSO Survey. We confirm the absence of spectral differences between radio-loud and radio-quiet quasars at rest-frame wavelengths longward of 1600 Å, as reported by previous authors. However, at shorter wavelengths we find a significant difference: radio-loud quasars have narrower (96% confidence), higher equivalent width (97% confidence) Lyman-α and C IV emission lines. We further investigate quasars which are radio quiet, but have radio-to-optical flux ratios at the upper extreme of the radio-quiet population. Broad absorption line quasars are overabundant by a factor of ∼10 in this radio-moderate population; the overabundance is significant at a 99.99% confidence level.

UR - http://www.scopus.com/inward/record.url?scp=0001732407&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001732407&partnerID=8YFLogxK

M3 - Article

VL - 106

SP - 417

EP - 425

JO - Astronomical Journal

JF - Astronomical Journal

SN - 0004-6256

IS - 2

ER -