5 papers · 1 filter
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…
Exotic sources detected in the 1 Ms Chandra Deep Field North Survey
D. M. Alexander, F. E. Bauer, W. N. Brandt +4
We provide constraints on optically faint (I>=24) X-ray sources, z>6 AGN, Very Red Objects (VROs; I-K>=4), and optically faint radio sources using the 1 Ms Chandra Deep Field North…