English
Related papers

Related papers: Hot Dust Clouds with Pure Graphite Composition aro…

200 papers

An integral part of the Unified Model for Active Galactic Nuclei (AGNs) is an axisymmetric obscuring medium, which is commonly depicted as a torus of gas and dust surrounding the central engine. However, a robust, dynamical model of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 S. K. Keating , J. E. Everett , S. C. Gallagher , R. P. Deo

We present an analysis of deep mid- to far-infrared (MFIR) Spitzer photometric observations of the southern 2Jy sample of powerful radio sources (0.05 < z < 0.7), conducting a statistical investigation of the links between radio jet, AGN,…

Astrophysics · Physics 2011-02-11 D. Dicken , C. Tadhunter , D. Axon , R. Morganti , K. J. Inskip , J. Holt , R. Gonzalez Delgado , B. Groves

Obscured AGN represent a significant fraction of the entire AGN population, especially at high redshift (~70% at z=3--5). They are often characterized by the presence of large gas and dust reservoirs that are thought to sustain and possibly…

The dusty environments (= "dust tori'') of AGN are now in reach of observations. Following our paper I on ground-based mid-IR spectro-photometry (H\"onig et al. 2010), we present an upgrade to our radiative transfer model of 3-dimensional…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. F. Hoenig , M. Kishimoto

Most of the optically classified low ionisation narrow emission-line regions (LINERs) nuclei host an active galactic nuclei (AGN). However, how they fit into the unified model (UM) of AGN is still an open question. The aims of this work are…

We present upper limits on the 850 micron and 450 micron fluxes of the warm hyperluminous (bolometric luminosity L_bol > 10^13 L_sun galaxies IRAS P09104+4109 (z=0.442) and IRAS F15307+3252 (z=0.926), derived from measurements using the…

Astrophysics · Physics 2016-01-13 J. R. Deane , Neil Trentham

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…

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 obscured AGN, based…

We present new mid-infrared (MIR) diagnostics to distinguish emission of active galactic nuclei (AGN) from that originating in starburst regions. Our method uses empirical spectroscopic criteria based on the fact that MIR emission from star…

We present measurements of black hole (BH) properties of 861 Type-1 active galactic nuclei (AGNs) in the North Ecliptic Pole (NEP)-Wide field. These AGNs are detected in both optical and mid-infrared (MIR) surveys and are identified as…

Submillimetre (sub-mm) galaxies have very high infrared (IR) luminosities and are thousands of times more numerous at z~2 than local ultra-luminous IR galaxies. They therefore represent a key phase in galaxy evolution which can be missed in…

Astrophysics · Physics 2007-05-23 Alexandra Pope , Ranga-Ram Chary , Mark Dickinson , Douglas Scott

To elucidate the intrinsic broadband infrared (IR) emission properties of active galactic nuclei (AGNs), we analyze the spectral energy distributions (SEDs) of 87 z<0.5 Palomar-Green (PG) quasars. While the Elvis AGN template with a…

Astrophysics of Galaxies · Physics 2017-02-06 Jianwei Lyu , G. H. Rieke , Yong Shi

We report the relationship between the luminosities of active galactic nuclei (AGNs) and the rates of star formation (SF) for a sample of 323 far-infrared (FIR)-detected AGNs. This sample has a redshift range of 0.2 $< z <$ 2.5, and spans…

We have obtained high-resolution mid-infrared (MIR) imaging, nuclear spectral energy distributions (SEDs) and archival Spitzer spectra for 22 low-luminosity active galactic nuclei (LLAGN; L_bol < 5 x 10^42 erg/s). Infrared (IR) observations…

Using the multi-epoch mid-infrared (MIR) photometry from the Wide-field Infrared Survey Explorer spanning a baseline of $\sim10$ yr, we extensively investigate the MIR variability of nearby active galactic nuclei (AGNs) at $0.15 < z < 0.4$.…

Astrophysics of Galaxies · Physics 2023-10-11 Suyeon Son , Minjin Kim , Luis C. Ho

(abridged) We present deep Spitzer mid-infrared spectroscopy, along with 16, 24, 70, and 850um photometry, for 22 galaxies located in GOODS-N. The sample spans a redshift range of 0.6 < z < 2.6, 24um flux densities between ~0.2-1.2 mJy, and…

Unified schemes of active galactic nuclei (AGN) require an obscuring dusty torus around the central source, giving rise to Seyfert 1 line spectrum for pole-on viewing and Seyfert 2 characteristics in edge-on sources. Although the observed…

Astrophysics · Physics 2009-11-07 M. Nenkova , Z. Ivezic , M. Elitzur

Type 2 AGN are by definition nuclei in which the broad-line region and continuum light are hidden at optical/UV wavelengths by dust. Via accurate registration of infrared (IR) Very Large Telescope adaptive optics images with optical…

Astrophysics of Galaxies · Physics 2015-06-19 M. A. Prieto , M. Mezcua , J. A. Fernández-Ontiveros , M. Schartmann

We present the X-ray analysis of the most luminous obscured active galactic nuclei (AGN) inside local ultraluminous infrared galaxies (ULIRGs). Our sample consists of ten sources, harbouring AGN components with estimated luminosity in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 E. Nardini , G. Risaliti

We analyse 2,015 mid-infrared (MIR) spectra of galaxies observed with Spitzer's Infrared Spectrograph, including objects with growing super-massive black holes and objects where most of the infrared emission originates from newly formed…

Astrophysics of Galaxies · Physics 2019-10-01 Erini L. Lambrides , Andreea O. Petric , Kirill Tchernyshyov , Nadia L. Zakamska , Duncan J. Watts
‹ Prev 1 4 5 6 7 8 10 Next ›