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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 ...
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 ...
The BeppoSAX View of the X‐Ray Active Nucleus of NGC 4258
(IOP Publishing, 2001)
BeppoSAX observed the Seyfert 1.9 galaxy NGC 4258 in 1998 December, when its 2-10 keV luminosity was about 1041 ergs s-1. Large amplitude (100%) variability is observed in the 3-10 keV band on timescales of a few tens of ...
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 ...
Chandra Multiwavelength Project: Normal Galaxies at Intermediate Redshift
(IOP Publishing, 2006)
We have investigated 136 Chandra extragalactic sources, including 93 galaxies with narrow emission lines (NELGs) and 43 with only absorption lines (ALGs). Based on fX/fO, LX, X-ray spectral hardness, and optical emission-line ...
X‐Ray and Optical Variability in NGC 4051 and the Nature of Narrow‐Line Seyfert 1 Galaxies
(IOP Publishing, 2000)
We report on the results of a three-year program of coordinated X-ray and optical monitoring of the narrow-line Seyfert 1 galaxy NGC 4051. The rapid continuum variations observed in the X-ray spectra are not detected in ...
X-ray absorption and re-emission from an ionized outflow in the Type 1 quasi-stellar object 2MASS 234449+1221 observed by XMM-Newton
(Oxford University Press (OUP), 2005)
We report on the analysis of a short XMM-Newton observation of the reddened Type 1 QSO 2MASS 234449+1221 first identified in the Two Micron All-Sky Survey. The underlying X-ray continuum is found to be typical of a broad-line ...
XMM‐Newton Observations of the Red Type 1.8 Quasar 2M1049+5837: Reflection from Cold and Warm (Ionized) Matter
(IOP Publishing, 2008)
Chandra observations of the type 1.8, low-redshift (z = 0.115), red (J − KS ~ 2) quasar 2MASSJ 104943+583750 (2M1049+5837) indicated an unusually hard X-ray spectrum (HR ~ 0.6), suggesting obscuration of NH ~ 4 × 1022 cm−2 ...