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The incidence and properties of Active Galactic Nuclei (AGN) in the field, groups, and clusters can provide new information about how these objects are triggered and fueled, similar to how these environments have been employed to study…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Timothy J. Arnold , Paul Martini , John S. Mulchaey , Angela Berti , Tesla E. Jeltema

Recent models for the inner structure of active galactic nuclei (AGN) advocate the presence of a radiatively accelerated, dusty outflow launched from the outer regions of the accretion disk. Here we present the first near-infrared (near-IR)…

We consider five indicators for intrinsic AGN luminosity: the luminosities of the [OIII]$\lambda$5007 line, the [OIV]25.89$\mu$m line, the mid-infrared (MIR) continuum emission by the torus, and the radio and hard X-ray (E $>$ 10keV)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Stephanie M. LaMassa , Timothy M. Heckman , Andrew Ptak , Lucimara Martins , Vivienne Wild , Paule Sonnentrucker , Christy Tremonti

The motivation of the "unified model" is to explain the main properties of the large zoo of active galactic nuclei with a single physical object. The discovery of broad permitted lines in the polarized spectrum of type 2 Seyfert galaxies in…

Astrophysics of Galaxies · Physics 2021-02-03 Luigi Spinoglio , Juan Antonio Fernández-Ontiveros

We have newly identified a substantial number of type 1 active galactic nuclei (AGN) featuring weak broad-line regions (BLRs) at z < 0.2 from detailed analysis of galaxy spectra in the Sloan Digital Sky Survey Data Release 7. These objects…

Astrophysics of Galaxies · Physics 2015-07-15 Kyuseok Oh , Sukyoung K. Yi , Kevin Schawinski , Michael Koss , Benny Trakhtenbrot

Context: The counts of galaxies and AGN in the mid infra-red (MIR) bands are important instruments for studying their cosmological evolution. However, the classic spectral line ratios techniques can become misleading when trying to properly…

We present a statistical analysis of the mid-infrared (MIR) spectra of 248 luminous infrared (IR) galaxies (LIRGs) which comprise the Great Observatories All-sky LIRG Survey (GOALS) observed with the Infrared Spectrograph (IRS) on-board the…

Aims: In this paper, we aim to constrain the properties of dust structures in the central first parsecs of Active Galactic Nuclei (AGN). Our goal is to study the required optical depth and composition of different dusty and ionised…

Astrophysics of Galaxies · Physics 2018-05-02 Lucas Grosset , Daniel Rouan , Damien Gratadour , Didier Pelat , Jan Orkisz , Frédéric Marin , René Goosmann

Effectively finding and identifying active galactic nuclei (AGNs) in dwarf galaxies is an important step in studying black hole formation and evolution. In this work, we examine four mid-IR-selected AGN candidates in dwarf galaxies with…

Astrophysics of Galaxies · Physics 2025-01-20 Megan R. Sturm , Bayli Hayes , Amy E. Reines

Telescopes like Herschel and the Atacama Large Millimeter/submillimeter Array (ALMA) are creating new opportunities to study sources in the far infrared (FIR), a wavelength region dominated by cold dust emission. Probing cold dust in active…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Aden R. Draper , David R. Ballantyne

We present a spectroscopic and photometric analysis of a sample of 416,288 galaxies from the Sloan Digital Sky Survey (SDSS) matched to mid-infrared (mid-IR) data from the Wide-Field Infrared Survey Explorer (WISE). By using a new…

Astrophysics of Galaxies · Physics 2022-04-27 Raphael E. Hviding , Kevin N. Hainline , Marcia Rieke , Stéphanie Juneau , Jianwei Lyu , Ragadeepika Pucha

We review critically the evidence concerning the fraction of Active Galactic Nuclei (AGN) which appear as Type 2 AGN, carefully distinguishing strict Type 2 AGN from both more lightly reddened .Type 1 AGN, and from low excitation narrow…

Astrophysics of Galaxies · Physics 2010-02-10 A. Lawrence , M. Elvis

We present high-resolution Keck LWS SiC filter (10.5-12.9 micron) mid-IR (MIR) images and photometry of a sample of nearby LLAGN. All MIR images show extended emission on small scales (e.g. 90% maximum widths 18 - 106 pc) deep within the…

Astrophysics · Physics 2007-05-23 Bruce Grossan

We quantify the active galactic nucleus (AGN) contribution to the mid-infrared (mid-IR) and the total infrared (IR, 8-1000micron) emission in a complete volume-limited sample of 53 local luminous infrared galaxies (LIRGs). We decompose the…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-16 Almudena Alonso-Herrero , Miguel Pereira-Santaella , George H. Rieke , Dimitra Rigopoulou

The unification of active galactic nuclei (AGN) is a model that has been difficult to test due to the lack of knowledge on the intrinsic luminosities of the objects. We present a test were we probe the model by statistical investigation of…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-05 Beatriz Villarroel , Andreas Korn , Yoshiki Matsuoka

We present the broad-band Spectral Energy Distributions (SEDs) of the largest available highly (72%) complete spectroscopic sample of mid-infrared (MIR) selected galaxies and AGN at intermediate redshift. The sample contains 203…

We present high-resolution mid-infrared (MIR) imaging, nuclear spectral energy distributions (SEDs) and archival Spitzer spectra for 22 low-luminosity active galactic nuclei (LLAGN; Lbol \lesssim 10^42 erg/sec). Infrared (IR) observations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 R. E. Mason , E. Lopez-Rodriguez , C. Packham , A. Alonso-Herrero , N. A. Levenson , J. Radomski , C. Ramos Almeida , L. Colina , M. Elitzur , I. Aretxaga , P. F. Roche , N. Oi

We use infrared spectroscopy and photometry to empirically define the intrinsic, thermal infrared spectral energy distribution (i.e., 6-100 um SED) of typical active galactic nuclei (i.e., 2-10 keV luminosity, Lx=10^{42}-10^{44} ergs/s…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 J. R. Mullaney , D. M. Alexander , A. D. Goulding , Ryan C. Hickox

We present the 15 micron luminosity function of type 1 AGN (QSO + Seyfert 1). Our sample of 21 high-redshift sources is selected from the Preliminary Analysis catalogue in the S1 field of the European Large Area ISO Survey (ELAIS). To study…

We have compiled a complete extragalactic sample based on 25,000 deg^2 to a limiting flux of 3E-11 ergs/cm**2/sec (7,000 deg^2 to a flux limit of 1E-11 ergs/cm**2/sec) in the 20 - 40 keV band with INTEGRAL. We have constructed a detailed…

Astrophysics · Physics 2011-02-11 V. Beckmann , S. Soldi , C. R. Shrader , N. Gehrels , N. Produit
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