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Related papers: A Bayesian Analysis of SDSS J0914+0853, a Low-Mass…

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We present a multi-wavelength analysis of MCG+11-11-032, a nearby AGN with the unique classification of both a binary and a dual AGN candidate. With new Chandra observations we aim to resolve any dual AGN system via imaging data, and search…

Water megamaser emission at 22 GHz has proven to be a powerful tool for astrophysical studies of AGN allowing an accurate determination of the central black hole mass and of the accretion disc geometry and dynamics. However, after searches…

As an evolutionary phase of galaxies, active galactic nuclei (AGN) over a large range of redshift have been utilized for understanding cosmic evolution. In particular, the population and evolution of AGNs have been investigated through the…

Astrophysics of Galaxies · Physics 2019-01-02 Jaejin Shin , Richard. M. Plotkin , Jong-Hak Woo , Elena Gallo , John S. Mulchaey

The radio-emitting quasar SDSS J1425+3231 (z=0.478) was recently found to have double-peaked narrow [O III] optical emission lines. Based on the analysis of the optical spectrum, Peng et al. (2011) suggested that this object harbours a dual…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-24 S. Frey , Z. Paragi , T. An , K. E. Gabanyi

We report on an optical (SDSS) and X-ray (XMM) study of an optically selected sample of four dual AGN systems at projected separations of 30--60~kpc. All sources are detected in the X-ray band (0.3-10 keV); seven objects are optically…

Improving the capabilities of detecting faint X-ray sources is fundamental to increase the statistics on faint high-z AGN and star-forming galaxies. We performed a simultaneous Maximum Likelihood PSF fit in the [0.5-2] keV and [2-7] keV…

In this manuscript, we recheck the spectroscopic properties of SDSS J134733.36+121724.27 (4C+12.50), confirming the presence of the double-peaked [O~{\sc iii}]$\lambda\lambda4959,5007$\AA\ doublet and a broad H$\alpha$. The former likely…

Astrophysics of Galaxies · Physics 2025-11-11 PeiZhen Cheng , XingQian Chen , GuiLin Liao , Qi Zheng , Ying Gu , MuLin Chen , XueGuang Zhang

The bulk of X-ray spectroscopic studies of active galactic nuclei (AGN) are focused on local ($z < 0.1$) sources with low-to-moderate ($< 0.3$) Eddington ratio ($\lambda_\mathrm{Edd}$). It is then mandatory to overcome this limitation and…

Astrophysics of Galaxies · Physics 2023-04-03 M. Laurenti , F. Tombesi , F. Vagnetti , E. Piconcelli , M. Guainazzi , R. Middei

[abridged] We present point-source catalogs for the 4Ms Chandra Deep Field-South (CDF-S), which is the deepest Chandra survey to date and covers an area of 464.5 arcmin^2. We provide a main source catalog, which contains 740 X-ray point…

We present XMM observations of the AGN SDSS 1430-0011. The low S/N spectrum of this source obtained in a snap shot Chandra observation showed an unusually flat continuum. With the follow up XMM observations we find that the source spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 S. Mathur , E. C. Golowacz , R. Williams , R. Pogge , D. Fields , D. Grupe

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 the first public release of our Bayesian inference tool, Bayes-X, for the analysis of X-ray observations of galaxy clusters. We illustrate the use of Bayes-X by analysing a set of four simulated clusters at z=0.2-0.9 as they…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 M. Olamaie , F. Feroz , K. J. B. Grainge , M. P. Hobson , J. S. Sanders , R. D. E Saunders

In this manuscript, an interesting blue Active Galactic Nuclei (AGN) SDSS J154751.94+025550 (=SDSS J1547) is reported with very different line profiles of broad Balmer emission lines: double-peaked broad H$\beta$ but single-peaked broad…

Astrophysics of Galaxies · Physics 2022-03-30 XueGuang Zhang

In the manuscript, a candidate of sub-pc binary black hole (BBH) system is reported in SDSS J1257+2023 through different properties of broad Balmer emission lines. After subtractions of host galaxy contributions, Gaussian functions are…

Astrophysics of Galaxies · Physics 2023-08-02 XueGuang Zhang

Active galactic nuclei (AGN) are some of the most powerful objects in the Universe. For this reason, they can be observed up to high redshifts (z), giving valuable insights into the evolution of our Universe. However, high-z AGN are too…

High Energy Astrophysical Phenomena · Physics 2025-05-14 Alysa Rogers , Daniel Schwartz , Cristiana Spingola , Anna Barnacka

AIMS. This work addresses the AGN IR-selection dependency on intrinsic source luminosity and obscuration, in order to identify and charaterise biases which could affect conclusions in studies. METHODS. We study IR-selected AGN in the…

Astrophysics of Galaxies · Physics 2015-06-18 Hugo Messias , Jose M. Afonso , Mara Salvato , Bahram Mobasher , Andrew M. Hopkins

SDSS J015957.64+003310.5 is an X-ray selected, $z=0.31$ AGN from the Stripe 82X survey that transitioned from a Type 1 quasar to a Type 1.9 AGN between 2000 and 2010. This is the most distant AGN, and first quasar, yet observed to have…

The Two Micron All-Sky Survey (2MASS) has provided a uniform photometric catalog to search for previously unknown red AGN and QSOs. We have extended the search to the southern equatorial sky by obtaining spectra for 1182 AGN candidates…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Frank Masci , Roc Cutri , Paul Francis , Brant Nelson , John Huchra , D. Heath Jones , Matthew Colless , Will Saunders

Merger-remnant galaxies with kpc-scale separation dual active galactic nuclei (AGNs) should be widespread as a consequence of galaxy mergers and triggered gas accretion onto supermassive black holes, yet very few dual AGNs have been…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-19 Julia M. Comerford , Brian F. Gerke , Daniel Stern , Michael C. Cooper , Benjamin J. Weiner , Jeffrey A. Newman , Kristin Madsen , R. Scott Barrows