Emission Line Properties of the Large Bright Quasar Survey
Open Access
- 1 May 2001
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal Supplement Series
- Vol. 134 (1) , 35-51
- https://doi.org/10.1086/320362
Abstract
We present measurements of the optical/UV emission lines for a large homogeneous sample of 993 quasars from the Large Bright Quasar Survey. Our largely automated technique accounts for continuum breaks and galactic reddening, and we perform multicomponent fits to emission line profiles, including the effects of blended iron emission, and of absorption lines both galactic and intrinsic. Here we describe the fitting algorithm and present the results of line fits to the LBQS sample, including upper limits to line equivalent widths when warranted. The distribution of measured line parameters, principally Wλ and FWHM, are detailed for a variety of lines, including upper limits. We thus initiate a large-scale investigation of correlations between the high-energy continuum and emission lines in quasars, to be extended to complementary samples using similar techniques. High-quality, reproducible measurements of emission lines for uniformly selected samples will advance our understanding of active galaxies, especially in a new era of large surveys selected by a variety of complementary methods.Keywords
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This publication has 51 references indexed in Scilit:
- The Fe II problem in NLS1sNew Astronomy Reviews, 2000
- On the Nature of Soft X‐Ray Weak Quasi‐stellar ObjectsThe Astrophysical Journal, 2000
- Locally Optimally Emitting Clouds and the Origin of Quasar Emission LinesThe Astrophysical Journal, 1995
- Data Reduction and Error Analysis for the Physical Sciences, 2nd ed.American Journal of Physics, 1993
- The emission-line properties of low-redshift quasi-stellar objectsThe Astrophysical Journal Supplement Series, 1992
- The large, bright QSO survey. IV - QSOs in two equatorial fieldsThe Astronomical Journal, 1991
- The relationship between infrared, optical, and ultraviolet extinctionThe Astrophysical Journal, 1989
- Relation between the ionizing continuum and the emission lines in Fairall 9The Astrophysical Journal, 1989
- A survey of interstellar H I from L-alpha absorption measurements. IIThe Astrophysical Journal, 1978
- Luminosity Indicators in the Spectra of Quasi-Stellar ObjectsThe Astrophysical Journal, 1977