Emission line properties of the Large Bright Quasar Survey

TY - JOUR

T1 - Emission line properties of the Large Bright Quasar Survey

AU - Forster, Karl

AU - Green, Paul J.

AU - Aldcroft, Thomas L.

AU - Vestergaard, M.

AU - Foltz, Craig B.

AU - Hewett, Paul C.

PY - 2001/5/1

Y1 - 2001/5/1

N2 - 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.

AB - 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.

KW - Galaxies: Active

KW - Quasars: Emission lines

KW - Quasars: General

KW - Ultraviolet: Galaxies

UR - http://www.scopus.com/inward/record.url?scp=0040001918&partnerID=8YFLogxK

U2 - 10.1086/320362

DO - 10.1086/320362

M3 - Review

AN - SCOPUS:0040001918

SN - 0004-637X

VL - 134

SP - 35

EP - 51

JO - Astrophysical Journal

JF - Astrophysical Journal

IS - 1

ER -