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Related papers: X-ray Detected AGN in SDSS Dwarf Galaxies

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We explore the role of the group environment in the evolution of AGN at the redshift interval 0.7<z<1.4, by combining deep Chandra observations with extensive optical spectroscopy from the All-wavelength Extended Groth strip International…

Astrophysics · Physics 2009-11-13 A. Georgakakis , Brian F. Gerke , K. Nandra , E. S. Laird , A. L. Coil , M. C. Cooper , J. A. Newman

Utilizing Chandra X-ray observations in the All-wavelength Extended Groth Strip International Survey (AEGIS) we identify 241 X-ray selected Active Galactic Nuclei (AGNs, L > 10^{42} ergs/s) and study the properties of their host galaxies in…

X-ray luminosity functions (XLFs) of Active Galactic Nuclei (AGN) trace the growth and evolution of supermassive black hole populations across cosmic time, however, current XLF models are poorly constrained at redshifts of z>6, with a lack…

High Energy Astrophysical Phenomena · Physics 2023-01-25 Cassandra L. Barlow-Hall , Jack Delaney , James Aird , Philip A. Evans , Julian P. Osborne , Michael G. Watson

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 present a census of local active galactic nuclei (AGN) at a redshift of $z\leq0.025$ selected using the high-ionization [Ne v] $\lambda14.32\,\mu$m emission line from the Infrared Database of Extragalactic Observables from Spitzer…

Astrophysics of Galaxies · Physics 2026-03-16 S. Yassir , A. Annuar

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…

Merger events can trigger gas accretion onto supermassive black holes (SMBHs) located at the centre of galaxies, and form close pairs of AGN. The fraction of AGN in pairs offers critical insights into the dynamics of galaxy interactions,…

We present an analysis of the X-ray properties of 35 submm galaxies(SMGs) in the CDF-N. Using a sample of robust 850micron-selected galaxies, with accurate positions from Spitzer and/or radio counterparts, we find 16 objects (45+/-8%) with…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Elise S. Laird , Kirpal Nandra , Alexandra Pope , Douglas Scott

We have used XMM-Newton to observe six Lyman Break Analogs (LBAs): members of the rare population of local galaxies that have properties that are very similar to distant Lyman Break Galaxies. Our six targets were specifically selected…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Jianjun Jia , Andrew Ptak , Timothy M. Heckman , Roderik A. Overzier , Ann Hornschemeier , Stephanie M. LaMassa

(ABRIDGED) AIMS: We searched for X-ray signatures of AGN in a sample of star-forming, relatively early-type, nearby spiral galaxies. Such galaxies are likely to host nuclear super-massive black holes. METHODS: For 9 sources from the Ho et…

Astrophysics · Physics 2008-11-26 P. Tzanavaris , I. Georgantopoulos

We explore the characteristics of actively accreting MBHs within dwarf galaxies in the \textsc{Romulus25} cosmological hydrodynamic simulation. We examine the MBH occupation fraction, x-ray active fractions, and AGN scaling relations within…

Astrophysics of Galaxies · Physics 2022-09-07 Ray S. Sharma , Alyson M. Brooks , Michael Tremmel , Jillian Bellovary , Angelo Ricarte , Thomas R. Quinn

SMBHs are theorised to undergo significant growth in the early Universe, however, the X-ray Luminosity Function (XLF), used as a principal tracer of the SMBH accretion density, lacks observational constraints at z>6, until now. We present…

High Energy Astrophysical Phenomena · Physics 2025-06-23 C. L. Barlow-Hall , J. Aird

We define a sample of 62 galaxies in the Chandra Deep Field-North whose Spitzer IRAC SEDs exhibit the characteristic power-law emission expected of luminous AGN. We study the multiwavelength properties of this sample, and compare the AGN…

Astrophysics · Physics 2011-02-11 J. L. Donley , G. H. Rieke , P. G. Perez-Gonzalez , J. R. Rigby , A. Alonso-Herrero

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

Searching for active galactic nuclei (AGN) in dwarf galaxies is important for our understanding of the seed black holes that formed in the early Universe. Here, we test infrared selection methods for AGN activity at low galaxy masses. Our…

Astrophysics of Galaxies · Physics 2016-12-07 Kevin N. Hainline , Amy E. Reines , Jenny E. Greene , Daniel Stern

The active galactic nuclei X-ray luminosity function traces actively accreting supermassive black holes and is essential for the study of the properties of the active galactic nuclei (AGN) population, black hole evolution, and galaxy-black…

The study of morphology in galaxies offers a convenient and quantitative method to measure the shapes and characteristics of galaxy light distribution that reflect the evolutionary history. For AGN-host dwarf galaxies, however, there is a…

Astrophysics of Galaxies · Physics 2025-06-09 Jie Tian , Yinghe Zhao , Xiejin Li , Jinming Bai

Hard X-ray selection is the most efficient way to discriminate between accretion-powered sources, such as AGN, from sources dominated by starlight. Hard X-rays are also less affected than other bands by obscuration. We have then carried out…

Astrophysics · Physics 2009-10-31 F. Fiore , F. La Franca , P. Giommi , M. Elvis , G. Matt , A. Comastri , S. Molendi , I. Gioia

We report on Chandra X-ray observations of four candidate low-mass black hole (<10^6Msun) active galactic nuclei (AGNs) that have the estimated Eddington ratios among the lowest (~10^(-2)) found for this class. The aims are to validate the…

Astrophysics of Galaxies · Physics 2015-06-18 W. Yuan , H. Zhou , L. Dou , X. -B. Dong , X. Fan , T. -G. Wang

We present an analysis of the X-ray Active Galactic Nucleus (AGN) population in a sample of seven massive galaxy clusters in the redshift range $0.35<z<0.45$. We utilize high-quality Chandra X-ray imaging to robustly identify AGN and…

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