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Exploring the variable sky with the Sloan Digital Sky Survey
(American Astronomical Society - The Astronomical Journal, 2007-12)
We quantify the variability of faint unresolved optical sources using a catalog
based on multiple SDSS imaging observations. The catalog covers SDSS Stripe
82, which lies along the celestial equator in the Southern ...
The host galaxies of luminous quasars
(Blackwell Publishing, 2004-11)
We present the results of a deep HST/WFPC2 imaging study of 17 quasars at z~=0.4, designed to determine the properties of their host galaxies. The sample consists of quasars with absolute magnitudes in the range −24 ≥ MV ...
A large, uniform sample of X-ray emitting AGN from the ROSAT All-Sky and Sloan Digital Sky Surveys: the Data Release 5 Sample
(American Astronomical Society - The Astronomical Journal, 2003-11)
We describe further results of a program aimed to yield ∼104 fully characterized optical
identifications of ROSAT X-ray sources. Our program employs X-ray data from the ROSAT
All-Sky Survey (RASS), and both optical imaging ...
A large, uniform sample of X-ray emitting AGN: selection approach and an initial catalog from the ROSAT All-Sky and Sloan Digital Sky Surveys
(American Astronomical Society - The Astronomical Journal, 2003-11)
Many open questions in X-ray astronomy are limited by the relatively small number
of objects in uniform optically-identified and observed samples, especially when rare
subclasses are considered, or when subsets are ...
A comparative HST imaging study of the host galaxies of radio-quiet quasars, radio-loud quasars and radio galaxies: I
(Blackwell Publishing, 1999-09)
We present the first results from a major HST WFPC2 imaging study aimed at providing the first statistically meaningful comparison of the morphologies, luminosities, scalelengths and colours of the host galaxies of radio-quiet ...