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

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We present the analysis and results of a spectroscopic follow-up program of a mass-selected sample of six galaxies at 3 < z < 4 using data from Keck-NIRSPEC and VLT-Xshooter. We confirm the z > 3 redshifts for half of the sample through the…

We use bulge-type classifications of 809 representative SDSS galaxies by Gadotti (2009) to classify a large sample of galaxies into real bulges (classical or elliptical) and pseudobulges using Random Forest. We use structural and stellar…

Astrophysics of Galaxies · Physics 2020-02-05 Hassen M. Yesuf , S. M. Faber , David C. Koo , Joanna Woo , Joel R. Primack , Yifei Luo

Active Galactic Nuclei (AGN) are axisymmetric systems to first order; their observed properties are likely strong functions of inclination with respect to our line of sight, yet the specific inclinations of all but a few AGN are generally…

Astrophysics of Galaxies · Physics 2015-06-18 T. C. Fischer , D. M. Crenshaw , S. B. Kraemer , H. R. Schmitt , T. J. Turner

We present a sample of 10 low-mass active galactic nuclei (AGNs) selected from the 40-month NuSTAR serendipitous survey. The sample is selected to have robust NuSTAR detections at $3 - 24$~keV, to be at $z < 0.3$, and to have optical r-band…

We searched the Northern Hemisphere Fields of the GALEX Time-Domain Survey (TDS) for galaxies with UV variability indicative of active galactic nuclei (AGNs). We identified 48 high-probability candidate AGNs from a parent sample of 1819…

Astrophysics of Galaxies · Physics 2024-05-31 Erik J. Wasleske , Vivienne F. Baldassare , Christopher M. Carroll

We present the first results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a cross-correlation of the ROSAT All Sky Survey (RASS) bright…

Astrophysics · Physics 2007-05-23 W. Pietsch , Th. Boller , S. Doebereiner , H. -U. Zimmermann , K. Bischoff , W. Kollatschny

The Swift Burst Alert Telescope (BAT) survey of Active Galactic Nuclei (AGN) is providing an unprecedented view of local AGNs (<z> = 0.03) and their host galaxy properties. In this paper, we present an analysis of the optical spectra of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Lisa M. Winter , Karen T. Lewis , Michael Koss , Sylvain Veilleux , Brian Keeney , Richard F. Mushotzky

We present some of the first science data with the new Keck/MOSFIRE instrument to test the effectiveness of different AGN/SF diagnostics at z~1.5. MOSFIRE spectra were obtained in three H-band multi-slit masks in the GOODS-S field,…

We use observations from the 9 square degree multiwavelength survey in Bootes to identify hundreds of obscured active galactic nuclei (AGN) with high redshifts (z > 0.7), luminosities (L_bol > 10^45 ergs/s), and moderate obscuring columns…

We present the results of optical spectroscopic identifications of a bright subsample of 2-10keV hard X-ray selected sources from the ASCA Medium Sensitivity Survey in the northern sky. The flux limit of the subsample is 3*10^-13 erg s^-1…

Astrophysics · Physics 2009-11-10 Masayuki Akiyama , Yoshihiro Ueda , Kouji Ohta , Tadayuki Takahashi , Toru Yamada

We present the identification and analysis of an unbiased sample of AGN that lie within the local galaxy population. Using the MPA-JHU catalogue (based on SDSS DR8) and 3XMM DR7 we define a parent sample of 25,949 local galaxies ($z \leq…

Astrophysics of Galaxies · Physics 2021-12-15 Keir L. Birchall , M. G. Watson , J. Aird , R. L. C. Starling

Context. A defining characteristic of active galactic nuclei (AGN) that distinguishes them from other astronomical sources is their stochastic variability, which is observable across the entire electromagnetic spectrum. Upcoming optical…

Active galactic nuclei (AGN) are supermassive black holes with luminous accretion disks found in some galaxies, and are thought to play an important role in galaxy evolution. However, traditional optical spectroscopy for identifying AGN…

Astrophysics of Galaxies · Physics 2022-12-16 Ziting Guo , John F. Wu , Chelsea E. Sharon

We present results from a study to detect variable galaxies in the Hubble Deep Field North. The goal of this project is to investigate the number density of AGN at z=1 through the detection of variable galaxy nuclei. The advantage of HST is…

Astrophysics · Physics 2009-10-31 V. L. Sarajedini , R. L. Gilliland , M. M. Phillips

Kiloparsec-scale dual active galactic nuclei (AGNs) are active supermassive black hole pairs co-rotating in galaxies with separations of less than a few kpc. Expected to be a generic outcome of hierarchical galaxy formation, their frequency…

Astrophysics of Galaxies · Physics 2018-07-23 Xin Liu , Hengxiao Guo , Yue Shen , Jenny E. Greene , Michael A. Strauss

X-rays offer a reliable method to identify Active Galactic Nuclei (AGN). However, in the high-redshift Universe X-ray AGN are poorly sampled due to their relatively low space density and the small areas covered by X-ray surveys. In addition…

We have employed a reliable technique of classification of Active Galactic Nuclei (AGN) based on the fit of well-sampled spectral energy distributions (SEDs) with a complete set of AGN and starburst galaxy templates. We have compiled…

We present new estimates on the fraction of heavily X-ray obscured, Compton-thick (CT) active galactic nuclei (AGNs) out to a redshift of $z \leq$ 0.8. From a sample of 540 AGNs selected by mid-IR (MIR) properties in observed X-ray survey…

Herein, we present the statistical properties of active galactic nuclei (AGNs) for approximately 1 million member galaxies of galaxy groups and clusters, with 0.1 $<$ cluster redshift ($z_{\rm cl}$) $<$ 1.4, selected using Subaru Hyper…

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