activity
19972005
most citedThe HELLAS2XMM 1dF survey: on the nature of high X-ray to optical flux ratio sources

1 citations · 1 across the 7 of their papers we have counts for

collaborators
Showing 2002Show all

6 papers · 1 filter

astro-ph2002

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…

astro-ph2002

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…

astro-ph2002

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…

astro-ph2002

An XMM-Newton survey of Extremely Red Objects

M. Brusa, A. Comastri, E. Daddi +2

We present preliminary results of a 25 ks XMM-Newton observation of the largest sample of Extremely Red Objects (EROs) available to date (about 450 sources), selected in a contiguo…

astro-ph2002

Chandra and XMM-Newton Observations of the Highest Redshift Quasars: X-rays from the Dawn of the Modern Universe

W. N. Brandt, C. Vignali, X. Fan +2

We review X-ray studies of the highest redshift (z > 4) quasars, focusing on recent advances enabled largely by the capabilities of Chandra and XMM-Newton. Included are discussions…

astro-ph2002

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…