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Related papers: Narrow-line AGN in the ISO-2MASS Survey

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Through an optical campaign performed at 4 telescopes located in the northern and the southern hemispheres, plus archival data from two on-line sky surveys, we have obtained optical spectroscopy for 29 counterparts of unclassified or poorly…

We present the emission properties of a sample of 3,579 type 1 AGN, selected based on the detection of broad H-alpha emission. The sample covers the range of black hole mass 10^6<M_BH/M_Sun<10^9.5 and luminosity in Eddington units 10^-3 <…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-23 Jonathan Stern , Ari Laor

We queried the Spitzer archive for high-resolution observations with the Infrared Spectrograph of optically selected active galactic nuclei (AGN) for the purpose of identifying sources with resolved fine-structure lines that would enable…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-21 K. M. Dasyra , L. C. Ho , H. Netzer , F. Combes , B. Trakhtenbrot , E. Sturm , L. Armus , D. Elbaz

We use a combination of the XMM-Newton serendipitous X-ray survey with the optical SDSS, and the infrared WISE all-sky survey in order to check the efficiency of the low X-ray to infrared luminosity selection method in finding heavily…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 E. Rovilos , I. Georgantopoulos , A. Akylas , J. Aird , D. M. Alexander , A. Comastri , A. Del Moro , P. Gandhi , A. Georgakakis , C. M. Harrison , J. R. Mullaney

The spectral energy distributions and infrared (IR) spectra of a sample of obscured AGNs selected in the mid-IR are modeled with recent clumpy torus models to investigate the nature of the sources, the properties of the obscuring matter,…

Astrophysics · Physics 2010-03-19 M. Polletta , D. Weedman , S. Hoenig , C. J. Lonsdale , H. E. Smith , J. Houck

We present results of optical identification of the ASCA Large Sky Survey. X-ray sources which have hard X-ray spectra were identified with type-2 AGN at redshifts smaller than 0.5. It is supported that the absorbed X-ray spectrum of type-2…

Astrophysics · Physics 2021-07-14 M. Akiyama , K. Ohta , T. Yamada , Y. Ueda , T. Takahashi , M. Sakano , T. Tsuru , I. Lehmann , G. Hasinger

We present the results of deep near-infrared observations of 11 hard X-ray selected sources in the Hellas2XMM survey, with faint optical magnitude (R>24) and high X-ray-to-optical flux ratio. All but one of the sources have been detected in…

We report the results of near infrared observations of 19 soft X-ray selected AGN. The goal of the observations was to search for strong, narrow Paschen-alpha or Brackett-gamma emission lines, as a sign of nuclear starbursts. We found…

Astrophysics · Physics 2009-11-07 D. Grupe , H. -C Thomas

Context: Finding Active Galactic Nuclei (AGN) behind the Magellanic Clouds (MCs) is difficult because of the high stellar density in these fields. Although the first AGN behind the Small Magellanic Cloud (SMC) were reported in the 1980s, it…

High Energy Astrophysical Phenomena · Physics 2019-01-30 C. Maitra , F. Haberl , V. D. Ivanov , Maria-Rosa L. Cioni , Jacco Th. van Loon

We have developed an efficient Active Galactic Nucleus (AGN) selection method using 18-band Spectral Energy Distribution (SED) fitting in mid-infrared (mid-IR). AGNs are often obscured by gas and dust, and those obscured AGNs tend to be…

Astrophysics of Galaxies · Physics 2017-08-29 Ting-Chi Huang , Tomotsugu Goto , Tetsuya Hashimoto , Nagisa Oi , Hideo Matsuhara

The Swift Burst Alert Telescope (BAT) survey of Active Galactic Nuclei (AGN) is providing an unprecedented view of local AGNs (<z> = 0.03) and their host galaxy properties. In this paper, we present an analysis of the optical spectra of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Lisa M. Winter , Karen T. Lewis , Michael Koss , Sylvain Veilleux , Brian Keeney , Richard F. Mushotzky

We report X-ray constraints for 20 of 52 high-z ULIRGs identified in the Spitzer xFLS to constrain their obscuration. Notably, decomposition of Spitzer-IRS spectra for the 52 objects already indicates that most are weak-PAH ULIRGs dominated…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 F. E. Bauer , Lin Yan , A. Sajina , D. M. Alexander

We present X-ray and optical analysis of 188 AGN identified from 497 hard X-ray (f (2.0-8.0 keV) > 2.7x10^-15 erg cm^-2 s^-1) sources in 20 Chandra fields (1.5 deg^2) forming part of the Chandra Multi-wavelength Project. These medium depth…

We present the results of an optical spectroscopic survey of 46 heavily obscured quasar candidates. Objects are selected using their mid-infrared (mid-IR) colours and magnitudes from the Wide-Field Infrared Survey Explorer (WISE) and their…

Astrophysics of Galaxies · Physics 2017-12-27 R. E. Hviding , R. C. Hickox , K. N. Hainline , C. M. Carroll , M. A. DiPompeo , W. Yan , M. L. Jones

We have analyzed the emission line properties of 6019 Type II AGN at redshifts between 0.4-0.8 with [OIII] luminosities greater than 3x10^8 Lsun, characteristic of the Type II quasars first identified in population studies by Zakamska et al…

Astrophysics of Galaxies · Physics 2019-09-25 Guinevere Kauffmann , Claudia Maraston

Previous surveys for HI 21-cm absorption in z > 0.1 radio galaxies and quasars yield a 40% detection rate, which is attributed to unified schemes of active galactic nuclei (AGN). In this paradigm absorption is only witnessed in (close to)…

Astrophysics · Physics 2008-08-01 S. J. Curran , M. T. Whiting , J. K. Webb

We report on the near-infrared selected AGN candidates extracted from 2MASS/ROSAT catalogues and discuss their properties. First, near-infrared counterparts of a X-ray source in ROSAT catalogues (namely, Bright Source Catalogue (BSC) and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Shinjirou Kouzuma , Hitoshi Yamaoka

The maximum number density of Active Galactic Nuclei (AGNs), as deduced from X-ray studies, occurs at z<~1, with lower luminosity objects peaking at smaller redshifts. Optical studies lead to a different evolutionary behaviour, with a…

Astrophysics · Physics 2009-11-13 D. Trevese , F. Vagnetti , S. Puccetti , F. Fiore , M. Tomei , M. A. Bershady

We develop a new diagnostic method to classify galaxies into AGN hosts, star-forming galaxies, and absorption-dominated galaxies by combining the [O III]/Hbeta ratio with rest-frame U-B color. This can be used to robustly select AGNs in…

We present an all-sky sample of ~ 1.4 million AGNs meeting a two color infrared photometric selection criteria for AGNs as applied to sources from the Wide-Field Infrared Survey Explorer final catalog release (AllWISE). We assess the…

Astrophysics of Galaxies · Physics 2015-11-04 Nathan Secrest , Rachel Dudik , Bryan Dorland , Norbert Zacharias , Valeri Makarov , Alan Fey , Julien Frouard , Charlie Finch
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