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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 ...
An Empirical Ultraviolet Template for Iron Emission in Quasars as Derived from I Zwicky 1
(IOP Publishing, 2001)
We present an empirical template spectrum suitable for fitting and subtracting/studying the Fe II and Fe III emission lines in the rest frame ultraviolet spectra of quasars and active galactic nuclei, the first empirical ...
Monitoring of the optical and 2.5 – 11.7 µm spectrum and mid-IR imaging of the Seyfert 1 galaxy Mrk 279 with ISO
(EDP Sciences, 2001)
Mid-infrared images of the Seyfert 1 galaxy Mrk 279 obtained with the ISO satellite are presented together with the results of a one-year monitoring campaign of the 2.5-11.7 micron spectrum. Contemporaneous optical photometric ...
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 ...
XMM‐Newton Observations of Red AGNs
(IOP Publishing, 2005)
XMM-Newton spectra of five red 2MASS active galactic nuclei (AGNs), selected from a sample observed by Chandra to be relatively X-ray bright and to cover a range of hardness ratios, confirm the presence of substantial ...
The Chandra X‐Ray Observatory Resolves the X‐Ray Morphology and Spectra of a Jet in PKS 0637-752
(IOP Publishing, 2000)
The core-dominated radio-loud quasar PKS 0637-752 (z = 0.654) was the first celestial object observed with the Chandra X-Ray Observatory, offering the early surprise of the detection of a remarkable X-ray jet. Several ...
Active Galactic Nucleus and Starburst Classification from Spitzer Mid‐Infrared Spectra for High‐Redshift SWIRE Sources
(IOP Publishing, 2006)
Spectra have been obtained with the Infrared Spectrograph (IRS) on the Spitzer Space Telescope for 20 sources in the Lockman Hole field of the SWIRE survey. The sample is divided between sources with indicators of an ...
What Do the Ultraviolet Spectra of Narrow‐Line Seyfert 1 Galaxies Tell Us about Their Broad‐Line Regions?
(IOP Publishing, 2000)
We study the UV spectra of narrow-line Seyfert 1 (NLSy1) galaxies and compare them with "normal" active galactic nuclei. Similar to their optical lines, the NLSy1s show narrower UV lines. They are also characterized by ...
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 ...