English
Related papers

Related papers: Mid-infrared Variability of Low-redshift Active Ga…

200 papers

We analyze JWST NIRSpec$+$MIRI/MRS observations of the infrared (IR) gas-phase molecular bands of the most enshrouded source (D1) within the interacting system and luminous IR galaxy II Zw 096. We report the detection of rovibrational lines…

Past studies of compact active galactic nuclei (AGNs), the dominant population at high radio frequencies, selected them using flat spectral index criteria. This biases the sample due to the steepening of AGN spectra at high radio…

Astrophysics of Galaxies · Physics 2020-03-04 R. Chhetri , A. Kimball , R. D. Ekers , E. K. Mahony , E. M. Sadler , T. Jarrett

We estimate the abundance of Compton-thick (CT) active galactic nuclei (AGN) based on our joint model of X-ray and infrared backgrounds. At L_{rest 2-10 keV} > 10^42 erg/s, the CT AGN density predicted by our model is a few 10^-4 Mpc^-3…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Yong Shi , George Helou , Lee Armus

Deep surveys of {\em Chandra} and {\em HST} (Hubble Space Telescope) show that active galactic nucleus (AGN) populations are changing with hard X-ray luminosities. This arises an interesting question whether the dusty torus is evolving with…

Astrophysics · Physics 2009-11-11 J. -M. Wang , E. P. Zhang , B. Luo

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

The obscuring circumnuclear torus of dusty molecular gas is one of the major components of active galactic nuclei (AGN). The torus can be studied by analyzing the time response of its infrared (IR) dust emission to variations in the AGN…

Astrophysics of Galaxies · Physics 2017-09-22 Triana Almeyda , Andrew Robinson , Michael Richmond , Billy Vazquez , Robert Nikutta

The covering factor of Compton-thick obscuring material associated with the torus in active galactic nuclei (AGN) is at present best understood through the fraction of sources exhibiting Compton-thick absorption along the line of sight…

We study the properties of 975 active galactic nuclei (AGN) selected by variability in the Pan-STARRS1 Medium-Deep Survey. Using complementary multi wavelength data from the ultraviolet to the far-infrared, we use SED fitting to determine…

Astrophysics of Galaxies · Physics 2016-07-27 S. Heinis , S. Gezari , S. Kumar , W. S. Burgett , H. Flewelling , M. E. Huber , N. Kaiser , R. J. Wainscoat , C. Waters

Using a complete, magnitude-limited sample of active galaxies from the Sloan Digital Sky Survey (SDSS) we show that the fraction of broad-line (Type 1) active galactic nuclei increases with luminosity of the isotropically-emitted [O III]…

Astrophysics · Physics 2009-11-10 Chris Simpson

In this paper, we investigate the robustness of WISE mid-IR color selection (W1-W2) for identifying obscured (Type 2) active galactic nuclei (AGNs) at low redshift (z<0.3), using a sample of ~360,000 SDSS galaxies classified via emission…

We present our statistical study of near infrared (NIR) variability of X-ray selected Active Galactic Nuclei (AGN) in the COSMOS field, using UltraVISTA data. This is the largest sample of AGN light curves in YJHKs bands, making possible to…

Astrophysics of Galaxies · Physics 2017-11-15 P. Sánchez , P. Lira , R. Cartier , V. Pérez , N. Miranda , C. Yovaniniz , P. Arévalo , B. Milvang-Jensen , J. Fynbo , J. Dunlop , P. Coppi , S. Marchesi

In order to better understand how active galactic nuclei (AGN) effect the interstellar media of their host galaxies, we perform a meta-analysis of the CO emission for a sample of $z=0.01-4$ galaxies from the literature with existing CO…

Astrophysics of Galaxies · Physics 2019-07-10 Allison Kirkpatrick , Chelsea Sharon , Erica Keller , Alexandra Pope

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…

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

We investigate the infrared contribution from supermassive black hole activity versus host galaxy emission in the mid to far-infrared (IR) spectrum for a large sample of X-ray bright active galactic nuclei (AGN) residing in dusty,…

Astrophysics of Galaxies · Physics 2019-07-02 Arianna Brown , Hooshang Nayyeri , Asantha Cooray , Jingzhe Ma , Ryan C. Hickox , Mojegan Azadi

Dedicated searches generally find a decreasing fraction of obscured Active Galactic Nuclei (AGN) with increasing AGN luminosity. This has often been interpreted as evidence for a decrease of the covering factor of the AGN torus with…

High Energy Astrophysical Phenomena · Physics 2017-05-31 S. Mateos , F. J. Carrera , X. Barcons , A. Alonso-Herrero , A. Hernán-Caballero , M. Page , C. Ramos Almeida , A. Caccianiga , T. Miyaji , A. Blain

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 study variability of active galactic nuclei (AGNs) by using the deep optical multiband photometry data obtained from the Hyper Suprime-Cam Subaru Strategic Program (HSC SSP) survey in the COSMOS field. The images analyzed here were taken…

Astrophysics of Galaxies · Physics 2020-05-13 Yuki Kimura , Toru Yamada , Mitsuru Kokubo , Naoki Yasuda , Tomoki Morokuma , Tohru Nagao , Yoshiki Matsuoka

The nature of the interaction between active galactic nuclei (AGNs) and their host galaxies remains an unsolved question. Therefore, conducting an AGN census is valuable to AGN research. Nevertheless, a significant fraction of AGNs are…

We investigate the radial structure of active galactic nuclei (AGN) dusty tori by forward-modeling mid-infrared (MIR) spectra observed with JWST/MIRI-MRS for a sample of 25 AGN. We develop a physically motivated three dimensional radiative…

Astrophysics of Galaxies · Physics 2026-03-17 Ruiyu Pan , Arkaprabha Sarangi