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

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We use Chandra data to study the incidence and properties of Active Galactic Nuclei (AGN) in 16 intermediate redshift ($0.5 < z < 1.1$) X-ray-selected galaxy groups in the Chandra Deep Field-South. We measure an AGN fraction of $f(L_{X,H} >…

The unified model of active galactic nuclei (AGN) claims that the properties of AGN depend on the viewing angle of the observer with respect to a toroidal distribution of dust surrounding the nucleus. Both the mid-infrared (MIR) attenuation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 O. Gonzalez-Martin , J. M. Rodriguez-Espinosa , T. Diaz-Santos , C. Packham , A. Alonso-Herrero , P. Esquej , C. Ramos Almeida , R. Mason , C. Telesco

Reliable, versatile galaxy activity diagnostics are essential for understanding galaxy evolution. Traditional methods frequently necessitate extensive preprocessing, such as starlight subtraction and emission line deblending (e.g.,…

Astrophysics of Galaxies · Physics 2026-02-25 C. Daoutis , A. Zezas , E. Kyritsis , K. Kouroumpatzakis , P. Bonfini

We use multi-band spatially resolved photometry from the Cosmic Assembly Near-IR Deep Legacy Survey (CANDELS) in the 4 MSec Chandra Deep Field-South (CDF-S) to explore the nuclear and extended colors, color gradients and stellar populations…

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 measurement of the fraction of cluster galaxies hosting X-ray bright Active Galactic Nuclei (AGN) as a function of clustercentric distance scaled in units of $r_{500}$. Our analysis employs high quality Chandra X-ray and Subaru…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 S. Ehlert , A. von der Linden , S. W. Allen , W. N. Brandt , Y. Q. Xue , B. Luo , A. Mantz , R. G. Morris , D. Applegate , P. Kelly

We present the results of a 2-epoch variability survey in the Hubble Deep Field with the goal of investigating the population of AGN to z=1. The primary data sets analyzed for galactic variability are the original HDF observations obtained…

Astrophysics · Physics 2009-11-10 Vicki L. Sarajedini , Ronald L. Gilliland , Christina Kasm

Active galactic nuclei (AGN) are typically identified through their distinctive X-ray or radio emissions, mid-infrared (MIR) colors, or emission lines. However, each method captures different subsets of AGN due to signal-to-noise (SNR)…

We present initial results from a Hubble Space Telescope snapshot imaging survey of the host galaxies of Swift-BAT active galactic nuclei (AGN) at z<0.1. The hard X-ray selection makes this sample sample relatively unbiased in terms of…

Astrophysics of Galaxies · Physics 2021-10-12 Minjin Kim , Aaron J. Barth , Luis C. Ho , Suyeon Son

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

In order to perform a more complete census of active galactic nuclei (AGN) in the local Universe, we investigate the use of the HeII~$\lambda 4685$ emission line diagnostic diagram by Shirazi & Brinchmann (2012) in addition to the standard…

Astrophysics of Galaxies · Physics 2017-01-25 Rudolf Bär , Anna K. Weigel , Lia F. Sartori , Kyuseok Oh , Michael Koss , Kevin Schawinski

We present a composite machine learning framework to estimate posterior probability distributions of bulge-to-total light ratio, half-light radius, and flux for Active Galactic Nucleus (AGN) host galaxies within $z<1.4$ and $m<23$ in the…

(Abridged) We develop a novel technique to identify active galactic nuclei (AGNs) and study the nature of low-luminosity AGNs in the Sloan Digital Sky Survey. This is the first part of a series of papers and we develop a new, sensitive…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Masayuki Tanaka

Using Spitzer-IRS spectroscopy, we investigate the ubiquity of Active Galactic Nuclei (AGN) in a complete (~94%), volume-limited sample of the most bolometrically-luminous galaxies (L_IR > (0.3-20) x 10^10 L_sun) to D < 15 Mpc. Our analyses…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Andy Goulding , Dave Alexander

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 present a catalog of emission-line galaxies selected solely by their emission-line fluxes using a wide-field integral field spectrograph. This work is partially motivated as a pilot survey for the upcoming Hobby-Eberly Telescope Dark…

We present a sample of accreting supermassive black holes (SMBHs) in dwarf galaxies at $z<1$. We identify dwarf galaxies in the NEWFIRM Medium Band Survey with stellar masses $M_{\star}<3\times 10^{9} M_{\odot}$ that have spectroscopic…

In this study, we present a modelling of the X-ray emission from the simulated SMBHs within the cosmological hydrodynamical Magneticum Pathfinder Simulation, in order to study the statistical properties of the resulting X-ray Active…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 V. Biffi , K. Dolag , A. Merloni