12 papers
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…
The Selection of RR Lyrae Stars Using Single-epoch Data
Zeljko Ivezic, A. Katherina Vivas, Robert H. Lupton +1
We utilize a complete sample of RR Lyrae stars discovered by the QUEST survey using light curves to design selection criteria based on SDSS colors. Thanks to the sensitivity of the…
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…
IR emission from AGNs
Moshe Elitzur, Maia Nenkova, Zeljko Ivezic
Unified schemes of active galactic nuclei (AGN) require an obscuring dusty torus around the central source, giving rise to type 1 line spectrum for pole-on viewing and type 2 chara…
An IR view of mass loss in Long Period Variables
Massimo Marengo, Margarita Karovska, Zeljko Ivezic
We have investigated the mass loss processes in Long Period Variables, by combining radiative transfer modeling with mid-IR imaging and spectroscopic observations. We find a correl…