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We investigate the infrared (IR) emission of high-redshift ($z\sim 6$), highly star-forming (${ {\rm SFR} > 100}$ $M_{\rm \odot} {\rm yr}^{-1}$) galaxies, with/without Active Galactic Nuclei (AGN), using a suite of cosmological simulations…

Astrophysics of Galaxies · Physics 2021-03-10 F. Di Mascia , S. Gallerani , C. Behrens , A. Pallottini , S. Carniani , A. Ferrara , P. Barai , F. Vito , T. Zana

We use quasi-simultaneous near-infrared (near-IR) and optical spectroscopy from four observing runs to study the continuum around 1 micron in 23 well-known broad-emission line active galactic nuclei (AGN). We show that, after correcting the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Hermine Landt , Martin Elvis , Martin J. Ward , Misty C. Bentz , Kirk T. Korista , Margarita Karovska

We present a new sample of active galactic nuclei (AGNs) identified using the catalog of the AKARI Mid-infrared(MIR) All-Sky Survey. Our MIR search has an advantage in detecting AGNs that are obscured at optical wavelengths due to…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-24 S. Oyabu , D. Ishihara , M. Malkan , H. Matsuhara , T. Wada , T. Nakagawa , Y. Ohyama , Y. Toba , T. Onaka , S. Takita , H. Kataza , I. Yamamura , M. Shirahata

Infrared-faint radio sources (IFRSs) are believed to be a rare class of radio-loud active galactic nuclei (RL AGN) characterized by their high radio-to-infrared flux density ratios of up to several thousands. Previous studies have shown…

Astrophysics of Galaxies · Physics 2025-02-11 Yihang Zhang , Lulu Fan , Tao An , Jun Yang , Weibin Sun , Haoran Yu , Yunkun Han

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…

The uncertainty surrounding the nature of the heating mechanism for the dust that emits at mid- to far-IR (MFIR) wavelengths in active galaxies limits our understanding of the links between active galactic nuclei (AGN) and galaxy evolution,…

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…

We study a combined sample of 264 star-forming, 51 composite, and 73 active galaxies using optical spectra from SDSS and mid-infrared (mid-IR) spectra from the Spitzer Infrared Spectrograph. We examine optical and mid-IR spectroscopic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Stephanie M. LaMassa , T. M. Heckman , A. Ptak , D. Schiminovich , M. O'Dowd , B. Bertincourt

We assume that dust near active galactic nuclei (AGN) is distributed in a torus-like geometry, which may be described by a clumpy medium or a homogeneous disk or as a combination of the two (i.e. a 2-phase medium). The dust particles…

Astrophysics of Galaxies · Physics 2015-11-11 Ralf Siebenmorgen , Frank Heymann , Andreas Efstathiou

Present AGN models aiming to account for the observed infrared SEDs consider a physical description of the dust and a solution of the radiative transfer problem. Mid infrared spectra obtained at different spatial scales are presented. They…

Astrophysics · Physics 2009-11-10 Ralf Siebenmorgen , Andreas Efstathiou

We use mid-infrared spectroscopy of unobscured active galactic nuclei (AGNs) to reveal their native dusty environments. We concentrate on Seyfert 1 galaxies, observing a sample of 31 with the Infrared Spectrograph aboard the Spitzer Space…

Astrophysics of Galaxies · Physics 2010-01-15 G. D. Thompson , N. A. Levenson , S. A. Uddin , M. M. Sirocky

We present deep {\it Spitzer} mid-infrared spectroscopy, along with 16, 24, 70, and 850\,$\micron$\ photometry, for 22 galaxies located in the Great Observatories Origins Deep Survey-North (GOODS-N) field. The sample spans a redshift range…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-06 E. J. Murphy , R. R. Chary , D. M. Alexander , M. Dickinson , B. Magnelli , G. Morrison , A. Pope , H. I. Teplitz

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…

Infrared observations of complete samples of active galactic nuclei (AGN) have shown that a substantial fraction of their bolometric luminosity is emitted at wavelengths ~8-1000microns. In radio-loud and Blazar-like objects much of this…

Astrophysics · Physics 2007-05-23 D. B. Sanders

The fraction of AGN luminosity obscured by dust and re-emitted in the mid-IR is critical for understanding AGN evolution, unification, and parsec-scale AGN physics. For unobscured (Type-1) AGN, where we have a direct view of the accretion…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 E. Lusso , J. F. Hennawi , A. Comastri , G. Zamorani , G. T. Richards , C. Vignali , E. Treister , K. Schawinski , M. Salvato , R. Gilli

Recent models for the inner structure of active galactic nuclei (AGN) aim at connecting the outer region of the accretion disk with the broad-line region and dusty torus through a radiatively accelerated, dusty outflow. Such an outflow not…

Astrophysics of Galaxies · Physics 2023-09-29 Hermine Landt

Forward modeling of the full galaxy SED is a powerful technique, providing self-consistent constraints on stellar ages, dust properties, and metallicities. However, the accuracy of these results is contingent on the accuracy of the model.…

Astrophysics of Galaxies · Physics 2018-02-28 Joel Leja , Benjamin D. Johnson , Charlie Conroy , Pieter van Dokkum

This work focuses on the properties of dusty tori in active galactic nuclei (AGN) derived from the comparison of SDSS type 1 quasars with mid-Infrared (MIR) counterparts and a new, detailed torus model. The infrared data were taken by the…

Astrophysics · Physics 2007-05-23 Evanthia Hatziminaoglou , the SWIRE Team

Recent near- and mid-infrared (IR) observations reveal the existence of appreciable amounts of aromatic and aliphatic hydrocarbon dust in the harsh environments of active galactic nuclei (AGNs), the origins of which are still under…

Astrophysics of Galaxies · Physics 2025-11-19 Risako Katayama , Hidehiro Kaneda , Takuma Kokusho , Tsubasa Kondo , Shinki Oyabu , Toyoaki Suzuki , Takuro Tsuchikawa

One of the remaining open issues in the context of the analysis of Active Galactic Nuclei (AGN) is the evidence that nuclear gravitational accretion is often accompanied by a concurrent starburst (SB) activity. What is, in this picture, the…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-22 Anna Feltre