Results 1 to 10 of about 53,582 (96)
Do Quasars Lens Quasars? [PDF]
The Astrophysical Journal, 1996 If the unexpectedly high frequency of quasar pairs with very different component redshifts is due to the lensing of a population of background quasars by the foreground quasar, typical lens masses must be $\sim10^{12}M_{\sun}$ and the sum of all such ...
Boyle B. J. +6 more
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A slitless spectroscopic survey for quasars near quasars [PDF]
Astronomy & Astrophysics, 2008 We present the results of the Quasars near Quasars (QNQ) survey, a CCD-based slitless spectroscopic survey for faint ...
Adelberger +96 more
core +5 more sources
Dust-free quasars in the early Universe
Nature, 2010 The most distant quasars known, at redshifts z=6, generally have properties indistinguishable from those of lower-redshift quasars in the rest-frame ultraviolet/optical and X-ray bands. This puzzling result suggests that these distant quasars are evolved
Linhua Jiang, Xiaohui Fan, W N Brandt
exaly +3 more sources
Quasar Clustering and the Lifetime of Quasars [PDF]
The Astrophysical Journal, 2001 ApJ Accepted (Feb 2001). 30 pages, 8 embedded ps figures, AASTEX5. Added discussion of quasar luminosity evolution. Also available at http://www.ociw.edu/~martini/pubs/
Paul Martini +2 more
openaire +4 more sources
Quasars Probing Quasars. X. The Quasar Pair Spectral Database [PDF]
The Astrophysical Journal Supplement Series, 2018 20 pages, 7 figures, 5 ...
J. Xavier Prochaska +11 more
openaire +8 more sources
Monthly Notices of the Royal Astronomical Society, 1999 Quasar pairs are either physically distinct binary quasars or the result of gravitational lensing. The majority of known pairs are in fact lenses, with a few confirmed as binaries, leaving a population of objects that have not yet been successfully classified.
Mortlock, D +2 more
openaire +5 more sources
THE PROPERTIES OF QUASAR HOSTS AT THE PEAK OF THE QUASAR ACTIVITY [PDF]
The Astrophysical Journal, 2009 We present near-infrared imaging obtained with ESO VLT/ISAAC of a sample of 16 low luminosity radio-quiet quasars at the epoch around the peak of the quasar activity (2 < z < 3), aimed at investigating their host galaxies. For 11 quasars, we are able to detect the host galaxies and derive their properties, while for the other five quasars, upper ...
Kotilainen J. K. +5 more
openaire +5 more sources
The Astrophysical Journal, 2002 In a survey of quasar candidates selected by matching the FIRST and 2MASS catalogs, we have found two extraordinarily red quasars. FIRST J013435.7-093102 is a 1 Jy source at z=2.216 and has B-K > 10, while FIRST J073820.1+275045 is a 2.5 mJy source at z=1.985 with B-K = 8.4.
Mark Lacy +9 more
openaire +3 more sources
The Quasar-LBG Two-point Angular Cross-correlation Function at z ~ 4 in the COSMOS Field [PDF]
, 2015 In order to investigate the origin of quasars, we estimate the bias factor for low-luminosity quasars at high redshift for the first time. In this study, we use the two-point angular cross-correlation function (CCF) for both low-luminosity quasars at ...
Akiyama, M. +17 more
core +3 more sources
Symposium - International Astronomical Union, 1994 I review recent results for quasars and discuss how they are related to activity in galaxies. Topics included are studies of quasar host galaxies with HST; searches for quasars in the Hubble Deep Field; evolution of the quasar luminosity function; news highlights from astro-ph; and current observational research problems and their relation to ...
openaire +3 more sources