Spectral Variability of Quasars in the Sloan Digital Sky Survey. II: The C IV Line

Details Spectral Variability of Quasars in the Sloan Digital Sky Survey. II: The C IV Line Spectral Variability of Quasars in the Sloan Digital Sky Survey. II: The C IV Line

2005-12-12

arxiv.org/abs/astro-ph/0512313v1

Astrophys.J.641:78-89,2006

Astronomy and Astrophysics

Astrophysics

52 pages, 14 figures, accepted for publication in ApJ

Scientific paper

10.1086/500421

We examine the variability of the high-ionizaton C IV line in a sample of 105 quasars observed at multiple epochs by the Sloan Digital Sky Survey. We find a strong correlation between the change in the C IV line flux and the change in the line width, but no correlations between the change in flux and changes in line center and skewness. The relation between line flux change and line width change is consistent with a model in which a broad line base varies with greater amplitude than the line core. The objects studied here are more luminous and at higher redshift than those normally studied for variability, ranging in redshift from 1.65 to 4.00 and in absolute r-band magnitude from roughly -24 to -28. Using moment analysis line-fitting techniques, we measure line fluxes, centers, widths and skewnesses for the C IV line at two epochs for each object. The well-known Baldwin Effect is seen for these objects, with a slope beta = -0.22. The sample has a median intrinsic Baldwin Effect slope of beta = -0.85; the C IV lines in these high-luminosity quasars appear to be less responsive to continuum variations than those in lower luminosity AGN. Additionally, we find no evidence for variability of the well known blueshift of the C IV line with respect to the low-ionization Mg II line in the highest flux objects, indicating that this blueshift might be useful as a measure of orientation.

Affiliated with

Also associated with

No associations

Rating

Spectral Variability of Quasars in the Sloan Digital Sky Survey. II: The C IV Line does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spectral Variability of Quasars in the Sloan Digital Sky Survey. II: The C IV Line, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spectral Variability of Quasars in the Sloan Digital Sky Survey. II: The C IV Line will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-35744