Are Optically-Selected QSO Catalogs Biased?
The Astronomical Journal, 1997 17 pages LaTeX (aasms4), plus 6 EPS figures.
Ferreras, Ignacio +2 more
openaire +3 more sources
Morphological Feature Distances among the Spectral Types of SDSS Galaxies
The Astrophysical JournalThis study investigates the morphological feature distances among various spectral types of galaxies from the Sloan Digital Sky Survey, including strong and weak active galactic nuclei (AGN), quasi-stellar objects (QSOs), quiescent, and star-forming ...
Duho Kim, Garreth Martin
doaj +1 more source
Spectroscopic Properties of QSOs Selected from Ultraluminous Infrared Galaxy Samples
, 2002 We performed spectroscopic observations for a large infrared QSO sample with a total of 25 objects. The sample was compiled from the QDOT redshift survey, the 1 Jy ULIRGs survey and a sample obtained by a cross-correlation study of the IRAS Point Source ...
Baker J. C. +15 more
core +1 more source
Q-SOS—A Sensor Observation Service for Accessing Quality Descriptions of Environmental Data
ISPRS International Journal of Geo-Information, 2015 The worldwide Sensor Web comprises observation data from diverse sources. Each data provider may process and assess datasets differently before making them available online. This information is often invisible to end users.
Anusuriya Devaraju +3 more
doaj +1 more source
The Cosmic Evolution and Spatial Distribution of Multiphase Gas Associated with QSOs
The Astrophysical Journal LettersWe investigate the multiphase gas surrounding QSOs traced by 33 absorption lines (e.g., Ly α , C iv , Fe ii , Mg ii , etc.) in the stacked spectra of background sources, using the Early Data Release from the Dark Energy Spectroscopic Instrument.
Zeyu Chen +12 more
doaj +1 more source
Studying the Flux Density of Bright Active Galaxies at Different Spectral Bands
مجلة بغداد للعلوم, 2019 Statistical studies are reported in this article for an active galactic nuclei sample of different type of active galaxies Seyferts 1, Seyferts 2, and Quasars. These sources have been selected from a Catalogue for bright X-ray galaxies.
Rashed et al.
doaj +1 more source
The X-ray Spectrum of the z=6.30 QSO SDSS J1030+0524
, 2004 We present a deep XMM-Newton observation of the z=6.30 QSO SDSS J1030+0524, the second most distant quasar currently known. The data contain sufficient counts for spectral analysis, demonstrating the ability of XMM-Newton to measure X-ray spectral shapes
D. Farrah +5 more
core +2 more sources
Spitzer Quasar and ULIRG evolution study (QUEST): I. The origin of the far infrared continuum of QSOs [PDF]
, 2006 This paper addresses the origin of the far-infrared (FIR) continuum of QSOs, based on the Quasar and ULIRG Evolution Study (QUEST) of nearby QSOs and ULIRGs using observations with the Spitzer Space Telescope. For 27 Palomar-Green QSOs at z
Baker, A. J. +15 more
core +3 more sources
The large, bright QSO survey. III - QSOs in six equatorial fields
The Astronomical Journal, 1991 This is the fourth paper in a series aimed at selecting about 1000 QSOs brighter than B(J) about 18.7 using machine-scanned direct and objective-prism plates from the UK Schmidt Telescope. The plate material is scanned at the Automated Plate Measuring facility.
Hewett, Paul C. +7 more
openaire +2 more sources
DESI Mg ii Absorbers: Extinction Characteristics and Quasar Redshift Accuracy
The Astronomical JournalIn this paper, we study how absorption-line systems affect the spectra and redshifts of quasi-stellar objects (QSOs), using catalogs of Mg ii absorbers from the early data release and first data release of the Dark Energy Spectroscopic Instrument.
Lucas Napolitano +34 more
doaj +1 more source