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Related papers: Identifying Active Galactic Nuclei at $z\sim3$ fro…

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We present a machine learning model to classify Active Galactic Nuclei (AGN) and galaxies (AGN-galaxy classifier) and a model to identify type 1 (optically unabsorbed) and type 2 (optically absorbed) AGN (type 1/2 classifier). We test…

Astrophysics of Galaxies · Physics 2021-12-08 Serena Falocco , Francisco J. Carrera , Josefin Larsson

We combine the Herschel Space Observatory PACS and SPIRE photometry with archival WISE photometry to construct the spectral energy distributions (SED) for over 300 local ($z < 0.05$), ultra-hard X-ray (14 - 195 keV) selected active galactic…

Astrophysics of Galaxies · Physics 2017-02-01 T. Taro Shimizu , Richard F. Mushotzky , Marcio Meléndez , Michael J. Koss , Amy J. Barger , Lennox L. Cowie

We present a machine-learning framework to accurately characterize morphologies of Active Galactic Nucleus (AGN) host galaxies within $z<1$. We first use PSFGAN to decouple host galaxy light from the central point source, then we invoke the…

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

High-redshift active galactic nuclei (AGN) serve as powerful probes of early black-hole growth, galaxy formation, and the evolving intergalactic medium (IGM). In this work, we use Lumina, a cosmological radiation-hydrodynamic simulation…

In a previous paper (Gavignaud et al. 2006), we presented the type-1 Active Galactic Nuclei (AGN) sample obtained from the first epoch data of the VIMOS-VLT Deep Survey (VVDS). The sample consists of 130 faint, broad-line AGN with redshift…

We discuss the spectral analysis of a sample of 63 Active Galactic Nuclei (AGN) detected above a limiting flux of $S(8-24$ keV$)=7\times10^{-14}$ erg/s/cm$^2$ in the multi-tiered NuSTAR Extragalactic Survey program. The sources span a…

Recent observations have revealed an interesting active galactic nuclei (AGN) subclass that shows strong activity at large scales ($\sim1$ kpc) but weaker at small scales ($<10$ pc), suggesting a strong change in the mass accretion rate of…

Astrophysics of Galaxies · Physics 2022-10-26 J. Pflugradt , K. Ichikawa , M. Akiyama , M. Kokubo , B. Vijarnwannaluk , H. Noda , X. Chen

We evaluate the underlying assumptions for the identification of Active Galactic Nuclei (AGNs) through near- and mid-infrared photometry and spectral energy distribution (SED) fitting out to z ~ 3. For massive galaxies, log(M) > 9.5, our…

We present a detailed analysis of the most luminous and obscured Active Galactic Nuclei (AGNs) detected in the ultra-hard X-ray band (14-195 keV) by Swift/BAT. Our sample comprises 21 X-ray luminous (log $L_X/{\rm erg\,s^{-1}}>44.6$, 2-10…

We introduce the Mass-Excitation (MEx) diagnostic to identify active galactic nuclei (AGN) in galaxies at intermediate redshift. In the absence of near-infrared spectroscopy, necessary to use traditional nebular line diagrams at z>0.4, we…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Stéphanie Juneau , Mark Dickinson , David M. Alexander , Samir Salim

We use the combination of the 2 Ms Chandra X-ray image, new J and H band images, and the Spitzer IRAC and MIPS images of the Chandra Deep Field-North to obtain high spectroscopic and photometric redshift completeness of high and…

Astrophysics · Physics 2009-11-13 A. J. Barger , L. L. Cowie

We present a catalog of physical properties for galaxies hosting active galactic nuclei (AGN) detected by the Wide-field Infrared Survey Explorer (WISE). By fitting broadband spectral energy distributions of sources in the WISE AGN Catalog…

Astrophysics of Galaxies · Physics 2021-12-08 R. Scott Barrows , Julia M. Comerford , Daniel Stern , Roberto J. Assef

Active galactic nuclei (AGNs) are the compact, energetic central regions of galaxies, powered by supermassive black holes that accrete surrounding gas and dust. Their optical spectra can be identified by strong emission-line signatures…

Astrophysics of Galaxies · Physics 2026-01-09 Sruthi Suresh , Wei Jeat Hon , Rachel L Webster , Christian Wolf , Christopher A Onken

This study explores the space density and properties of active galaxies to z=0.8. We have investigated the frequency and nature of unresolved nuclei in galaxies at moderate redshift as indicators of nuclear activity such as Active Galactic…

We assemble a broad-band spectral energy distribution (SED) ranging from optical to mid-infrared of nearby active galactic nuclei at $z < 0.4$. SED fitting analysis is performed using semi-empirical templates derived from Palomar-Green…

Astrophysics of Galaxies · Physics 2023-06-23 Suyeon Son , Minjin Kim , Luis C. Ho

We have completed a spectroscopic survey of X-ray point sources in eight low-redshift clusters of galaxies (0.05<z<0.31) and have identified 40 cluster members with broad-band (0.3-8 keV) X-ray luminosities between L_X = 8x10^{40} and…

Astrophysics · Physics 2009-11-11 Paul Martini , Daniel D. Kelson , Eunhyeuk Kim , John S. Mulchaey , Alex A. Athey

We present the Advanced Camera for Surveys Active Galactic Nuclei (ACS-AGN) Catalog, a catalog of 2585 active galactic nucleus (AGN) host galaxies that are at redshifts 0.2<z<2.5 and that were imaged with the Hubble Space Telescope's…

Astrophysics of Galaxies · Physics 2020-01-15 Aaron Stemo , Julia M. Comerford , R. Scott Barrows , Daniel Stern , Roberto J. Assef , Roger L. Griffith

We present a measure of the hard (2-8 keV) X-ray luminosity function (XLF) of Active Galactic Nuclei up to z~5. At high redshifts, the wide area coverage of the Chandra Multiwavength Project is crucial to detect rare and luminous (Lx >…