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Related papers: Silicate Dust in Active Galactic Nuclei

200 papers

The appearance of active galactic nuclei (AGN) depends so strongly on orientation that our current classification schemes are dominated by random pointing directions instead of more interesting physical properties. Light from the centers of…

Astrophysics · Physics 2011-07-18 C. Megan Urry , Paolo Padovani

Aims. In this paper we study the Spitzer and TIMMI2 infrared spectra of post-AGB disc sources, both in the Galaxy and the LMC. Using the observed infrared spectra we determine the mineralogy and dust parameters of the discs, and look for…

Solar and Stellar Astrophysics · Physics 2015-05-30 C. Gielen , J. Bouwman , H. Van Winckel , T. Lloyd Evans , P. M. Woods , F. Kemper , M. Marengo , M. Meixner , G. C. Sloan , A. G. G. M. Tielens

We analyze the mid-infrared (MIR) spectra of ultraluminous infrared galaxies (ULIRGs) observed with the Spitzer Space Telescope's Infrared Spectrograph. Dust emission dominates the MIR spectra of ULIRGs, and the reprocessed radiation that…

Astrophysics · Physics 2009-11-13 M. M. Sirocky , N. A. Levenson , M. Elitzur , H. W. W. Spoon , L. Armus

From extensive radiative transfer calculations we find that clumpy torus models with \No \about 5--15 dusty clouds along radial equatorial rays successfully explain AGN infrared observations. The dust has standard Galactic composition, with…

Astrophysics · Physics 2011-02-11 Maia Nenkova , Matthew M. Sirocky , Robert Nikutta , Zeljko Ivezic , Moshe Elitzur

Some high-z active galactic nuclei (AGNs) are found to reside in extreme star-forming galaxies, such as hyper-luminous infrared galaxies (HyLIRGs), with AGN-removed $L_{\rm{IR}}$ of $>10^{13} L_{\rm{\odot}}$. In this paper, we report NOEMA…

I present a generalized power-law diagnostic that allows to identify the presence of active galactic nuclei (AGN) in infrared (IR) galaxies at z>1, down to flux densities at which the extragalactic IR background is mostly resolved. I derive…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Karina I. Caputi

We present a 5-8 micron analysis of the Spitzer-IRS spectra of 71 ultraluminous infrared galaxies (ULIRGs) with redshift z < 0.15, devoted to the study of the role of active galactic nuclei (AGN) and starbursts (SB) as the power source of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 E. Nardini , G. Risaliti , M. Salvati , E. Sani , Y. Watabe , A. Marconi , R. Maiolino

Dust reprocesses the intrinsic radiation of active galactic nuclei (AGNs) to emerge at longer wavelengths. The observed mid-infrared (MIR) luminosity depends fundamentally on the luminosity of the central engine, but in detail it also…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 N. A. Levenson , J. T. Radomski , C. Packham , R. E. Mason , J. J. Schaefer , C. M. Telesco

The emission of warm dust dominates the mid-infrared spectra of active galactic nuclei (AGN). Only interferometric observations provide the necessary angular resolution to resolve the nuclear dust and to study its distribution and…

Following the discovery of SAGE0536AGN ($z \sim$ 0.14), with the strongest 10-$\mu$m silicate emission ever observed for an Active Galactic Nucleus (AGN), we discovered SAGE0534AGN ($z \sim$ 1.01), a similar AGN but with less extreme…

Studying absorption and scattering of X-ray radiation by interstellar dust grains allows us to access the physical and chemical properties of cosmic grains even in the densest regions of the Galaxy. We aim at characterising the dust…

In the last decades, several multiwavelength studies have been dedicated to exploring the properties of the obscuring material in active galactic nuclei (AGN). Various models have been developed to describe the structure and distribution of…

High quality infrared spectra of active galaxies including the stellar absorption features of Si at 1.59 um, CO(6,3) at 1.62 um, and CO(2,0) at 2.29 um are used to measure the stellar mass to light ratio at 1.65 um (M_H/L) and investigate…

Astrophysics · Physics 2007-05-23 E. Oliva , L. Origlia , R. Maiolino , A. F. M. Moorwood

Little red dots (LRDs) are a puzzling population of extragalactic sources whose origin is highly debated. In this {work}, we performed a comprehensive stacking analysis of NIRCam, MIRI, and ALMA images of a large and homogeneously selected…

Recent high angular resolution observations resolved for the first time the mid-infrared (MIR) structure of nearby active galactic nuclei (AGN). Surprisingly, they revealed that a major fraction of their MIR emission comes from the polar…

Astrophysics of Galaxies · Physics 2017-08-30 Marko Stalevski , Daniel Asmus , Konrad R. W. Tristram

The presence of the dust in the circumnuclear region strongly affects our view of the nucleus itself. The effect is strong in type 2 objects but weaker effect is likely to be present in type 1 objects as well. In these objects a correction…

Astrophysics · Physics 2007-05-23 B. Czerny

Several models of nuclear dust in active galactic nuclei (AGN) have been presented in the literature to determine its physical and geometrical properties, usually assuming the dust density distribution as the main aspect producing…

We present infrared, optical, and X-ray data of 48 X-ray bright, optically dull AGNs in the COSMOS field. These objects exhibit the X-ray luminosity of an active galactic nucleus (AGN) but lack broad and narrow emission lines in their…

X-ray emission detection in a galaxy is one of the efficient tools for selecting Active Galactic Nuclei (AGNs). However, many X-ray-selected AGNs are not easily selected as AGNs by their optical emission. These galaxies, so-called optically…

Astrophysics of Galaxies · Physics 2022-03-31 Itsna K. Fitriana , Takashi Murayama

The nucleus of the nearby galaxy, NGC 1097, is known to host a young, compact (r < 9 parsec) nuclear star cluster as well as a low-luminosity active galactic nucleus (AGN). It has been suggested both that the nuclear stellar cluster is…

Astrophysics · Physics 2011-02-11 R. E. Mason , N. A. Levenson , C. Packham , M. Elitzur , J. Radomski , A. O. Petric , G. S. Wright