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A Chandra Survey of Broad Absorption Line Quasars
(IOP Publishing, 2001)
We have carried out a survey with the Chandra X-Ray Observatory of a sample of 10 bright broad absorption line (BAL) quasars (QSOs). Eight of 10 sources are detected. The six brightest sources have only high-ionization ...
The reddest ISO-2MASS quasar
(EDP Sciences, 2007)
Context. While there is growing consensus on the existence of numerous dust-enshrouded red quasars, their discovery and detailed exploration is still an observational challenge. In the course of the near-mid-infrared AGN ...
XMM-Newton Observations of High-Redshift Quasars
(IOP Publishing, 2006)
We report on our XMM-Newton observations of the high-redshift quasars BR 2237-0607 (z = 4.558) and BR 0351-1034 (z = 4.351). We also report on XMM-Newton observations of 19 other z > 4 objects available in the public archive ...
Discovery of a z = 4.93, X-Ray-selected Quasar by the Chandra Multiwavelength Project (ChaMP)
(IOP Publishing, 2002)
We present X-ray and optical observations of CXOMP J213945.0-234655, a high-redshift (z = 4.93) quasar discovered through the Chandra Multiwavelength Project (ChaMP). This object is the most distant X-ray-selected quasar ...
The X-Ray Properties of 2MASS Red Active Galactic Nuclei
(IOP Publishing, 2002)
The Two Micron All Sky Survey is finding previously unidentified, luminous, red, active galactic nuclei (AGNs). This new sample has a space density similar to, or greater than, previously known AGNs, suggesting that a large ...
Comparison of high- and low-state X-ray spectra in the type 1.5 quasi-stellar object 2MASS 0918+2117
(Oxford University Press (OUP), 2007)
When observed by XMM–Newton in 2003, the type 1.5 quasi-stellar object 2MASS 0918+2117 was found to be in a low state, with an X-ray flux approximately four to five times fainter than during an earlier Chandra observation. ...
The ISO-2MASS AGN survey: on the type-1 sources
(EDP Sciences, 2005)
We combined the ISOCAM Parallel Mode Survey at 6.7 micron (LW2 filter) with the Two Micron All Sky Survey in order to obtain a powerful tool to search for AGN independent of dust extinction. Using moderate colour criteria ...
The Luminosity Function of X‐Ray–selected Active Galactic Nuclei: Evolution of Supermassive Black Holes at High Redshift
(IOP Publishing, 2008)
We present a measure of the hard (2-8 keV) X-ray luminosity function (XLF) of AGNs up to z ~ 5. At high redshifts, the wide area coverage of the Chandra Multiwavength Project is crucial to detect rare and luminous (LX > ...
Clustering of Red Galaxies around the Z = 1.53 Quasar 3C 270.1
(IOP Publishing, 2009)
In the paradigm of hierarchical galaxy formation, luminous radio galaxies mark mass assembly peaks that should contain clusters of galaxies. Observations of the z = 1.53 quasar 3C 270.1 with the Spitzer Space Telescope at ...
XMM-Newton Observations of Two High-Redshift Quasars: RX J1028-0844 and BR 0351-1034
(IOP Publishing, 2004)
We report the results of XMM-Newton observations of two high-redshift quasars, one radio-loud, RX J1028.6-0844 (z = 4.276) and one radio-quiet, BR 0351-1034 (z = 4.351). We find that the evidence for strong excess absorption ...