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Related papers: AGN Unification at z ~ 1: u - R Colors and Gradien…

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We present and discuss optical imaging of 76 AGN which represent the 2MASS-selected sample for z<0.3, from a full list of 243. They are found to have dust-obscured nuclei, residing in host galaxies that show a high fraction (>70%) of tidal…

Astrophysics · Physics 2009-11-07 J. B. Hutchings , N. Maddox , R. M. Cutri , B. O. Nelson

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

We quantify the presence of Active Galactic nuclei (AGN) in a mass-complete (M_* >5e10 M_sun) sample of 123 star-forming and quiescent galaxies at 1.5 < z < 2.5, using X-ray data from the 4 Ms Chandra Deep Field-South (CDF-S) survey.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Karen Pardos Olsen , Jesper Rasmussen , Sune Toft , Andrew W. Zirm

We present detailed image analysis of rest-frame optical images of 235 low-redshift ($z \leq$ 0.35) type 1 active galactic nuclei (AGNs) observed with the Hubble Space Telescope. The high-resolution images enable us to perform rigorous…

Astrophysics of Galaxies · Physics 2017-10-09 Minjin Kim , Luis C. Ho , Chien Y. Peng , Aaron J. Barth , Myungshin Im

We perform a statistical analysis of AGN host characteristics and nuclear activity for AGNs in pairs and without companions. Our study concerns a sample of AGNs derived from the SDSS-DR4 data by Kauffmann et al (2003) and pair galaxies…

Astrophysics · Physics 2008-11-26 M. Sol Alonso , Diego G. Lambas , Patricia Tissera , Georgina Coldwell

Kpc-scale dual and offset Active Galactic Nuclei (AGNs) are signposts of accreting supermassive black holes (SMBHs) triggered during late-stage galaxy mergers, offering crucial insights into the coevolution of SMBHs and galaxies. However,…

Astrophysics of Galaxies · Physics 2024-05-27 Junyao Li , Ming-Yang Zhuang , Yue Shen , Marta Volonteri , Nianyi Chen , Tiziana Di Matteo

We present a set of low resolution empirical SED templates for AGNs and galaxies in the wavelength range from 0.03 to 30 microns based on the multi-wavelength photometric observations of the NOAO Deep-Wide Field Survey Bootes field and the…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 R. J. Assef , C. S. Kochanek , M. Brodwin , R. Cool , W. Forman , A. H. Gonzalez , R. C. Hickox , C. Jones , E. Le Floc'h , J. Moustakas , S. S. Murray , D. Stern

We present a detailed X-ray spectral analysis of 1152 AGNs selected in the Chandra Deep Fields (CDFs), in order to identify highly obscured AGNs ($N_{\rm H} > 10^{23}\ \rm cm^{-2}$). By fitting spectra with physical models, 436 (38%)…

We study the host properties and environment of active galactic nuclei (AGNs) galaxies, taken from SDSS-DR12, across the $\text{[O III]}/\text{H}\beta$ vs $\text{[N II]}/\text{H}\alpha$ diagnostic diagram. We select AGN subsamples defined…

Astrophysics of Galaxies · Physics 2023-10-25 Noelia Perez , Georgina Coldwell

We present optical integral field spectroscopy for five $z<0.062$ narrow-line Seyfert 1 galaxies (NLS1s) host galaxies, probing their host galaxies at $\gtrsim 2-3$ kpc scales. Emission lines in the nuclear AGN spectra and the large-scale…

Astrophysics of Galaxies · Physics 2017-11-22 J. Scharwächter , B. Husemann , G. Busch , S. Komossa , M. A. Dopita

The role of galaxy mergers in fueling active galactic nuclei (AGN) is still debated, owing partly to selection effects inherent to studies of the merger/AGN connection. In particular, luminous AGN are often heavily obscured in late-stage…

Astrophysics of Galaxies · Physics 2018-07-23 Laura Blecha , Gregory F. Snyder , Shobita Satyapal , Sara L. Ellison

We identify sources with extremely hard X-ray spectra (i.e., with photon indices of Gamma<0.6 in the 13 sq. deg. NuSTAR serendipitous survey, to search for the most highly obscured AGNs detected at >10 keV. Eight extreme NuSTAR sources are…

Clusters of galaxies have long been used as laboratories for the study of galaxy evolution, but despite intense, recent interest in feedback between AGNs and their hosts, the impact of environment on these relationships remains poorly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 David W. Atlee , Paul Martini , Roberto J. Assef , Daniel D. Kelson , John S. Mulchaey

Observations with the James Webb Space Telescope (JWST) have uncovered numerous faint active galactic nuclei (AGN) at $z\sim5$ and beyond. These objects are key to our understanding of the formation of supermassive black holes (SMBHs),…

The origin of the ionizing photons that completed hydrogen reionization remains debated. Using recent JWST and ground-based surveys at 4.5 <= z <= 6.5, we construct a unified rest-UV AGN luminosity function that separates unobscured Type I…

Astrophysics of Galaxies · Physics 2025-11-03 Mainak Singha , Sangeeta Malhotra , James Ely Rhoads

We investigate active galactic nuclei (AGN) candidates within the FourStar Galaxy Evolution Survey (ZFOURGE) to determine the impact they have on star-formation in their host galaxies. We first identify a population of radio, X-ray, and…

We present infrared (IR) to X-ray spectral energy distributions (SEDs) for 44 red AGN selected from the 2MASS survey on the basis of their red J-K$_S$ color (>2 mag) and later observed by Chandra. In comparison with optically-, radio-, and…

We present new Chandra X-ray Observatory and Hubble Space Telescope observations of eight optically selected broad-line AGN candidates in nearby dwarf galaxies ($z<0.055$). Including archival Chandra observations of three additional…

High Energy Astrophysical Phenomena · Physics 2017-02-15 Vivienne F. Baldassare , Amy E. Reines , Elena Gallo , Jenny E. Greene

We have selected a sample of X-ray emitting active galactic nuclei (AGNs) in low-mass host galaxies (5e9-2e10 Msun) out to z~1. By comparing to AGNs in more massive hosts, we have found that the AGN spatial number density and the fraction…

Astrophysics · Physics 2009-11-13 Yong Shi , George Rieke , Jennifer Donley , Michael Cooper , Christopher Willmer , Evan Kirby

Nuclear starbursts may contribute to the obscuration of active galactic nuclei (AGNs). The predicted star formation rates are modest, and, for the obscured AGNs that form the X-ray background at z < 1, the associated faint radio emission…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 C. M. Pierce , D. R. Ballantyne , R. J. Ivison