20 papers
Infrared Number Counts of AGN in the GOODS Fields
E. Treister, C. Megan Urry, the GOODS AGN Team
Using the known numbers and evolution of unobscured AGN, and assuming that there is a large number of corresponding obscured AGN -- as expected if AGN unification is correct -- we…
The Power of Exploratory Chandra Observations
S. C. Gallagher, G. T. Richards, W. N. Brandt +1
With its excellent spatial resolution, low background, and hard-band response, the Chandra X-ray Observatory is ideal for performing exploratory surveys. These efficient, sensitive…
X-rays from the First Massive Black Holes
W. N. Brandt, C. Vignali, D. P. Schneider +7
X-ray studies of high-redshift (z > 4) active galaxies have advanced substantially over the past few years, largely due to results from the new generation of X-ray observatories. A…
Reverberation Mapping of High-Redshift, High-Luminosity Quasars
Shai Kaspi, Hagai Netzer, Dan Maoz +3
We present preliminary results from a reverberation mapping program to measure the Broad Line Region size in high-redshift, high-luminosity quasars. The observations are carried ou…
X-ray emission from the most luminous z>4 Palomar Digital Sky Survey Quasars: the Chandra view
C. Vignali, W. N. Brandt, D. P. Schneider +2
We present the results obtained from exploratory Chandra observations of nine high-redshift (z=4.09-4.51) quasars, selected from among the optically brightest Palomar Digital Sky S…
On the nature of Extremely Red Objects: the 2 Ms Chandra Deep Field-North Survey results
C. Vignali, D. M. Alexander, F. E. Bauer +4
Understanding the nature of Extremely Red Objects [EROs; (I-K)>=4] is one of the most challenging issues in observational cosmology. Here we report on the X-ray constraints provide…