20 papers · 1 filter
SDSS Quasars and Dust Reddening
Patrick B. Hall, Philip Hopkins, Michael Strauss +2
The Sloan Digital Sky Survey can be used to detect and characterize red and reddened quasars. In Richards et al. (2003), we showed that 6% of SDSS quasars have red colors consisten…
Constraints on Quasar Continuum, BELR, and BALR Physics from SDSS Composite Spectra
Gordon T. Richards, Patrick B. Hall, Timothy A. Reichard +3
We review recent results on quasars from the SDSS as they relate to our understanding of the UV/optical continuum, the broad emission line region, and the broad absorption line reg…
Type II Quasars from the SDSS
Nadia L. Zakamska, Michael A. Strauss, Julian H. Krolik +1
Type II quasars are suggested by unification models of Active Galactic Nuclei as luminous analogs of Seyfert 2 galaxies. A number of different methods have been used hitherto to di…
Quasar Radio Dichotomy: Two Peaks, or not Two Peaks, that is the Question
Z. Ivezic, G. T. Richards, P. B. Hall +8
Recent claims by Ivezic et al. (2002) that the distribution of the radio-to-optical flux ratio, R, for quasars is bimodal (the so-called quasar radio dichotomy) were questioned on…
Counts of Low-redshift SDSS Quasar Candidates
Z. Ivezic, R. H. Lupton, D. E. Johnston +10
We analyze the counts of low-redshift quasar candidates selected using nine-epoch SDSS imaging data. The co-added catalogs are more than 1 mag deeper than single-epoch SDSS data, a…
Halo Structure Traced by SDSS RR Lyrae
Z. Ivezic, R. H. Lupton, D. Schlegel +6
We discuss the density and radial velocity distributions of over 3000 candidate RR Lyrae stars selected by various methods using Sloan Digital Sky Survey data for about 1000 deg^2…