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Related papers: Automated algorithms to build Active Galactic Nucl…

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We present modeling and interpretation of the continuum and emission lines for a sample of 51 unobscured Type 1 active galactic nuclei (AGN). All of these AGNs have high quality spectra from both XMM-Newton and Sloan Digital Sky Survey…

High Energy Astrophysical Phenomena · Physics 2015-05-30 C. Jin , M. Ward , C. Done , J. M. Gelbord

Finding and characterizing the population of active galactic nuclei (AGNs) that produces the X-ray background (XRB) is necessary to connect the history of accretion to observations of galaxy evolution at longer wavelengths. The year 2012…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 D. R. Ballantyne , A. R. Draper , K. K. Madsen , J. R. Rigby , E. Treister

We present an estimate of the space density of Active Galactic Nuclei (AGN) at z=3. Combining deep X-ray data with Lyman Break Galaxy (LBG) colour-selection in the rest-frame UV makes for highly efficient identification of AGN in a narrow…

Astrophysics · Physics 2009-11-10 K. Nandra , E. S. Laird , C. C. Steidel

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 a method for automated classification of galaxies with low signal-to-noise (S/N) spectra typical of redshift surveys. We develop spectral simulations based on the parameters for the 2dF Galaxy Redshift Survey, and with these…

Astrophysics · Physics 2015-06-24 S. R. Folkes , O. Lahav , S. J. Maddox

In this study, we use the SWIFT/BAT AGN sample, which has received extensive multiwavelength follow-up analysis as a result of the BAT AGN Spectroscopic Survey (BASS), to develop a diagnostic for nuclear obscuration by examining the…

Approximately 3-17 percent of Active Galactic Nuclei (AGN) without detected rest-frame UV/optical broad emission lines (type-2 AGN) do not show absorption in X-rays. The physical origin behind the apparently discordant optical/X-ray…

Targeted searches for dual active galactic nuclei (AGN), with separations 1 -- 10 kpc, have yielded relatively few successes. A recent pilot survey by Satyapal et al. has demonstrated that mid-infrared (mid-IR) pre-selection has the…

Astrophysics of Galaxies · Physics 2017-07-26 Sara L. Ellison , Nathan J. Secrest , J. Trevor Mendel , Shobita Satyapal , Luc Simard

Classification of intermediate redshift ($z$ = 0.3--0.8) emission line galaxies as star-forming galaxies, composite galaxies, active galactic nuclei (AGN), or low-ionization nuclear emission regions (LINERs) using optical spectra alone was…

We have used very deep XMM-Newton observations of the Chandra Deep Field-South to examine the spectral properties of the faint active galactic nucleus (AGN) population. Crucially, redshift measurements are available for 84% (259/309) of the…

Astrophysics · Physics 2009-11-11 T. Dwelly , M. J. Page

The emission line luminosity function of active galactic nuclei (AGN) is measured from about 3000 AGN included in the main galaxy sample of the Sloan Digital Sky Survey within a redshift range of $0<z<0.15$. The $\Ha$ and [OIII]$\lambda…

We report the discovery using Spitzers high resolution spectrograph of 7 Active Galactic Nuclei (AGN) in a sample of 32 late-type galaxies that show no definitive signatures of AGN in their optical spectra. Our observations suggest that the…

Astrophysics · Physics 2009-11-13 S. Satyapal , D. Vega , R. P. Dudik , N. P. Abel , T. Heckman

We analyze the validity of optical diagnostic diagrams relying on emission-lines ratios and in the context of classifying Active Galactic Nuclei (AGNs) according to the cosmic metallicity evolution in the redshift range 0 < z < 11.2. In…

Astrophysics of Galaxies · Physics 2023-11-27 Oli L. Dors , M. V. Cardaci , G. F. Hagele , G. S. Ilha , C. B. Oliveira , R. A. Riffel , R. Riffel , A. C. Krabbe

We present the properties of active galactic nuclei (AGN) selected by optical variability in the Subaru/XMM-Newton Deep Field (SXDF). Based on the locations of variable components and light curves, 211 optically variable AGN were reliably…

We present the results from an X-ray spectral analysis of active galactic nuclei (AGN) in the Chandra Deep Field-South, AEGIS-XD and Chandra-COSMOS surveys, focussing on the identification and characterisation of the most heavily obscured,…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Murray Brightman , Kirpal Nandra , Mara Salvato , Li-Ting Hsu , Cyprian Rangel

This paper explores the application of machine learning methods for classifying astronomical sources using photometric data, including normal and emission line galaxies (ELGs; starforming, starburst, AGN, broad line), quasars, and stars. We…

The application of multi-wavelength selection techniques is crucial for discovering a complete and unbiased set of Active Galactic Nuclei (AGNs). Here, we select a sample of 72 AGN candidates in the Extended Groth Strip (EGS) using deep…

In this work we have updated the list of AGN detected by INTEGRAL taking into account the new objects listed in the last published INTEGRAL/IBIS survey. We have collected 83 new AGN increasing the number of INTEGRAL detected active galaxies…

High Energy Astrophysical Phenomena · Physics 2023-03-29 A. Malizia , L. Bassani , R. Landi , M. Molina , N. Masetti , E. Palazzi , G. Bruni , A. Bazzano , P. Ubertini , A. J. Bird

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
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