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Related papers: Local Active Galactic Nuclei with Large Broad-H{\a…

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We investigate how the fraction of broad-line sources in the AGN population changes with X-ray luminosity and redshift. We first construct the rest-frame hard-energy (2-8 keV) X-ray luminosity function (HXLF) at z=0.1-1 using Chandra…

Astrophysics · Physics 2009-11-10 A. T. Steffen , A. J. Barger , L. L. Cowie , R. F. Mushotzky , Y. Yang

We present here our results on the hour like time scale X-ray flux variations in a sample of active galactic nuclei using data from the Nuclear Spectroscopic Telescope Array (NuSTAR). We find that in the 3-79 keV band, BL Lacs are more…

High Energy Astrophysical Phenomena · Physics 2016-03-07 Priyanka Rani , C. S. Stalin

We present a study of 41 dwarf galaxies hosting active massive black holes (BHs) using Hubble Space Telescope observations. The host galaxies have stellar masses in the range of $M_\star \sim 10^{8.5}-10^{9.5}~M_\odot$ and were selected to…

Astrophysics of Galaxies · Physics 2021-05-05 Seth J. Kimbrell , Amy E. Reines , Zachary Schutte , Jenny E. Greene , Marla Geha

We analyze Hubble Space Telescope (HST) optical imaging of eight low-mass galaxies hosting active galactic nuclei (AGN) identified via their photometric variability in \cite{baldassare_search_2020}. We use GALFIT to model the 2D galaxy…

Astrophysics of Galaxies · Physics 2025-02-06 Erin Kimbro , Vivienne Baldassare , Guy Worthey , Marla Geha , Jenny Greene

We study the host galaxy properties of active galactic nuclei (AGN) that have been detected in X-rays in the nearby Universe ($\rm z<0.2$). For that purpose, we use the catalogue provided by the ROSAT-2RXS in the 0.1-2.4\,keV energy band,…

Astrophysics of Galaxies · Physics 2022-02-02 L. Koutoulidis , G. Mountrichas , I. Georgantopoulos , E. Pouliasis , M. Plionis

The co-evolution of host galaxies and the active black holes which reside in their centre is one of the most important topics in modern observational cosmology. Here we present a study of the properties of obscured Active Galactic Nuclei…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. Brusa , F. Fiore , P. Santini , A. Grazian , A. Comastri , G. Zamorani , G. Hasinger , A. Merloni , F. Civano , A. Fontana , V. Mainieri

We present a long temporal baseline variability survey in the Frontier Field MACSJ1149. In this study, we identify active galactic nuclei (AGNs) and other transient sources via their variability using over a decade of Hubble Space Telescope…

Astrophysics of Galaxies · Physics 2020-05-27 John Della Costa , Vicki L. Sarajedini , Louis-Gregory Strolger

Variability of active galactic nuclei (AGNs) has long been servicing as an essential avenue of exploring the accretion physics of black hole (BH). There are two commonly used methods for analyzing AGN variability. First, the AGN…

Astrophysics of Galaxies · Physics 2024-07-04 Zhen-Bo Su , Zhen-Yi Cai , Mouyuan Sun , Hengxiao Guo , Wei-Min Gu , Jun-Xian Wang

This paper reports results of the third-year campaign of monitoring super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs) between 2014-2015. Ten new targets were selected from quasar sample of Sloan…

We use mid-infrared variability in galaxies to search for active galactic nuclei (AGN) in the local universe. We use a sample of 10,220 galaxies from the Mapping Nearby Galaxies at APO (MaNGA) survey, part of the Sloan Digital Sky Survey…

Astrophysics of Galaxies · Physics 2024-12-09 Aashay Pai , Michael R. Blanton , John Moustakas

8.4-GHZ radio imaging study of an optically selected sample of early type Seyfert galaxies; comparison of images taken at two epochs reveals possible variation in the nuclear radio flux density in five of them over a seven year period. It…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-25 C. G. Mundell , N. Nagar , P. Ferruit

This is the fifth paper in a series of investigations of the clustering properties of luminous, broad-emission-line active galactic nuclei (AGN) identified in the ROSAT All-Sky Survey (RASS) and Sloan Digital Sky Survey (SDSS). In this work…

We present a model that explains some extreme variability phenomena observed in active galactic nuclei (AGN). In this model, an orbiting companion interacts with the accretion disk surrounding the central supermassive black hole (SMBH).…

High Energy Astrophysical Phenomena · Physics 2025-06-26 Sierra A. Dodd , Xiaoshan Huang , Shane W. Davis , Enrico Ramirez-Ruiz

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} >…

Changing-Look (CL) is a rare phenomenon of Active Galactic Nuclei (AGNs) that exhibit emerging or disappearing broad lines accompanied by continuum variations on astrophysically short timescales ($\lesssim$ 1 yr to a few decades). While…

Astrophysics of Galaxies · Physics 2019-12-12 Hengxiao Guo , Mouyuan Sun , Xin Liu , Tinggui Wang , Minzhi Kong , Shu Wang , Zhenfeng Sheng , Zhicheng He

We present NIR spectroscopy using MMT/MMIRS for a sample of twenty-nine massive galaxies ($\mathrm{log\ M_* / M_{\odot} \gtrsim10}$) at $\mathrm{z\sim0.7}$ with optical spectroscopy from the LEGA-C survey. Having both optical and NIR…

Almost all massive galaxies today are understood to contain supermassive black holes (SMBH) at their centers. SMBHs grew by accreting material from their surroundings, emitting X-rays as they did so. X-ray Luminosity Functions (XLFs) of…

Astrophysics of Galaxies · Physics 2023-01-16 Ahlam Alqasim , Mat J. Page

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. However, except for a few special cases, the specific inclinations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 T. C. Fischer , D. M. Crenshaw , S. B. Kraemer , H. R. Schmitt

We used random forest algorithms to classify all objects in a large portion of the sky, using optical light curves obtained, or built from images provided, by the Zwicky Transient Facility (ZTF). We compare different selection sets based on…

Astrophysics of Galaxies · Physics 2025-03-25 S. Bernal , P. Sánchez-Sáez , P. Arévalo , F. E. Bauer , P. Lira , B. Sotomayor

We present a catalog of Local Universe Near-Infrared Seyfert (LUNIS) \textit{K-}band integral field unit (IFU) data of 88 nearby Active Galactic Nuclei (AGN), curated from SINFONI/VLT and OSIRIS/Keck archival datasets. This catalog includes…

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