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Related papers: Candidate AGNs in Late-Type Galaxies

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We present a systematic X-ray study of eight AGNs with intermediate mass black holes (M_BH 8-95x10^4 Msun) based on 12 XMM-Newton observations. The sample includes the two prototype AGNs in this class - NGC4395 and POX52 and six other AGNs…

Astrophysics · Physics 2009-11-13 G. C. Dewangan , S. Mathur , R. E. Griffiths , A. R. Rao

A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically "elusive". X-ray observations are an optimal tool to identify this class of objects. We combine new…

(Abridged) A high fraction of the Low Mass X-ray Binaries (LMXBs) in early-type galaxies are associated with globular clusters (GCs). Here, we discuss the correlations between LMXBs and GCs in a sample of four early-type galaxies. There is…

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 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

Dust enshrouded activity can ideally be studied by mid-infrared (MIR) observations. In order to explore the AGN versus star forming origin of the nuclear MIR emission of galaxies, observations of high spatial resolution are required. Here…

Active galactic nuclei (AGNs) are the compact, energetic central regions of galaxies, powered by supermassive black holes that accrete surrounding gas and dust. Their optical spectra can be identified by strong emission-line signatures…

Astrophysics of Galaxies · Physics 2026-01-09 Sruthi Suresh , Wei Jeat Hon , Rachel L Webster , Christian Wolf , Christopher A Onken

The XMM-Newton survey of the Small Magellanic Cloud (SMC) revealed 3053 X-ray sources with the majority expected to be active galactic nuclei (AGN) behind the SMC. However, the high stellar density in this field often does not allow…

High Energy Astrophysical Phenomena · Physics 2015-06-16 R. Sturm , D. Drašković , M. D. Filipović , F. Haberl , J. Collier , E. J. Crawford , M. Ehle , A. De Horta , W. Pietsch , N. F. H. Tothill , G. Wong

Highly obscured active galactic nuclei (AGN) are common in nearby galaxies, but are difficult to observe beyond the local Universe, where they are expected to significantly contribute to the black hole accretion rate density. Furthermore,…

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) Since its launch in October 2002, the INTEGRAL satellite has revolutionized our knowledge of the hard X-ray sky thanks to its unprecedented imaging capabilities and source detection positional accuracy above 20 keV. Nevertheless,…

Using a suite of X-ray, mid-IR and optical active galactic nuclei (AGN) luminosity indicators, we search for Compton-thick (CT) AGNs with intrinsic L_X>10^42erg/s at z~0.03-0.2, a region of parameter space which is currently poorly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Andy Goulding , David Alexander , James Mullaney , Jonathan Gelbord , Ryan Hickox , Martin Ward , Mike Watson

We report a serendipitous discovery of six very low-luminosity active galactic nuclei (AGNs) only by optical variability in one-month baseline. The detected flux variability is ~ 1-5% of the total luminosity of host galaxies. Careful…

Astrophysics · Physics 2009-11-10 Tomonori Totani , Takahiro Sumi , George Kosugi , Naoki Yasuda , Mamoru Doi , Takeshi Oda

We present the X-ray spectral analysis of the 1855 extragalactic sources in the Chandra COSMOS-Legacy survey catalog having more than 30 net counts in the 0.5-7 keV band. 38% of the sources are optically classified Type 1 active galactic…

We present an analysis of the X-ray bright point source population in 43 massive clusters of galaxies observed with the Chandra X-ray Observatory. We have constructed a catalog of 4210 rigorously selected X-ray point sources in these…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 S. Ehlert , S. W. Allen , W. N. Brandt , Y. Q. Xue , B. Luo , A. von der Linden , A. Mantz , R. G. Morris

We aim to study the effect of environment on the presence and fuelling of Active Galactic Nuclei (AGN) in massive galaxy clusters. We explore the use of different AGN detection techniques with the goal of selecting AGN across a broad range…

Astrophysics of Galaxies · Physics 2015-06-05 Alison J. Klesman , Vicki L. Sarajedini

The low-mass end of the supermassive black hole mass function is unknown and difficult to determine. Here we discuss our successful program to find active nuclei of late type "normal" galaxies using X-ray detections and multiwavelength…

Astrophysics · Physics 2009-11-13 Smita Mathur , Himel Ghosh , Laura Ferrarese , Fabrizio Fiore

Deep Chandra X-ray exposures provide an efficient route for locating optically faint active galactic nuclei (AGN) at high redshifts. We use deep multicolor optical data to search for z>5 AGN in the 2 Ms X-ray exposure of the Chandra Deep…

We present an X-ray stacking analysis of $\sim$75,000 star-forming galaxies between $0.1<z<5.0$ using the Chandra COSMOS Legacy survey to study the X-ray emission of low-luminosity active galactic nuclei (AGN) and its connection to host…

High Energy Astrophysical Phenomena · Physics 2018-09-26 Francesca M. Fornasini , Francesca Civano , Giuseppina Fabbiano , Martin Elvis , Stefano Marchesi , Takamitsu Miyaji , Andreas Zezas

We searched the Chandra and XMM archives for observations of 900 green pea galaxies to find AGN signatures. Green peas are low-mass galaxies with prominent emission lines, similar in size and star formation rate to high-redshift dwarf…

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