English
Related papers

Related papers: Spatially-Offset AGN Candidates in the CLASS Surve…

200 papers

The nearby galaxy NGC 3115 contains a known radio-emitting, low-luminosity active galactic nucleus (AGN), and was recently claimed to host a candidate AGN displaced 14.3 pc from the galaxy's optical photocenter. Our goal is to understand…

Astrophysics of Galaxies · Physics 2019-04-03 Megan L. Jones , Sarah Burke-Spolaor , Kristina Nyland , Joan M. Wrobel

We have found compact, near-nuclear X-ray sources in 21 (54\%) of a complete sample of 39 nearby face-on spiral and elliptical galaxies with available ROSAT HRI data. ROSAT X-ray luminosities (0.2 $-$ 2.4 keV) of these compact X-ray sources…

Astrophysics · Physics 2009-10-30 E. J. M. Colbert , R. F. Mushotzky

Our goal is to characterize AGN populations by comparing their X-ray and optical classifications. We present a sample of 99 spectroscopically identified X-ray point sources in the XMM-LSS survey which are significantly detected in the…

(Abridged) We present the results from new 15 ks Chandra-ACIS and 4.9 GHz Very Large Array observations of 13 galaxies hosting low luminosity AGN. This completes the multiwavelength study of a sample of 51 nearby early-type galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Preeti Kharb , A. Capetti , D. J. Axon , M. Chiaberge , P. Grandi , A. Robinson , G. Giovannini , B. Balmaverde , D. Macchetto , R. Montez

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

Cheung identified a sample of 100 candidate X-shaped radio galaxies using the NRAO FIRST survey; these are small-axial-ratio extended radio sources with off-axis emission. Here we present radio images of 52 of these sources that have been…

Astrophysics of Galaxies · Physics 2015-09-16 David H. Roberts , Jake P. Cohen , Jing Lu , Lakshmi Saripalli , Ravi Subrahmanyan

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

This is the first of a series of three papers exploring the connection between the multiwavelength properties of AGNs in nearby early-type galaxies and the characteristics of their hosts. We selected two samples, both with high resolution 5…

Astrophysics · Physics 2009-11-13 Alessandro Capetti , Barbara Balmaverde

This work studies the correlation among environmental density and radio AGN presence up to $z = 2$. Using data from the photometric COSMOS survey and its radio 1.4 GHz follow-up (VLA-COSMOS), a sample of radio AGNs has been defined. The…

Astrophysics of Galaxies · Physics 2016-09-09 Nicola Malavasi , Sandro Bardelli , Paolo Ciliegi , Olivier Ilbert , Lucia Pozzetti , Elena Zucca

We present a study of X-ray AGN overdensities in 16 Abell clusters, within the redshift range 0.073<z<0.279, in order to investigate the effect of the hot inter-cluster environment on the triggering of the AGN phenomenon. The X-ray AGN…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-29 E. Koulouridis , M. Plionis

We present the X-ray data and the optical identifications for a deep ROSAT PSPC observation in the "Marano field". In the inner region of the ROSAT field (15' radius) we detected 50 X-ray sources with Sx >= 3.7x10^(-15) erg/cm^2/s. When…

Recently, Zakamska et al. (2003) selected 291 high-ionization narrow emission-line AGN in the redshift range 0.3-0.83 from the Sloan Digital Sky Survey spectroscopic data. The sample includes both Seyfert II galaxies and their higher…

Astrophysics · Physics 2009-11-10 C. Vignali , D. M. Alexander , A. Comastri

We present a large sample of 501 radio-selected BL Lac candidates from the combination of the Sloan Digital Sky Survey (SDSS) Data Release 5 optical spectroscopy and from the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) radio…

We present the clustering properties of a complete sample of 968 radio sources detected at 1.4 GHz by the VLA-COSMOS survey with radio fluxes brighter than 0.15 mJy. 92% have redshift determinations from the Laigle et al. (2016) catalogue.…

Astrophysics of Galaxies · Physics 2016-11-23 M. Magliocchetti , P. Popesso , M. Brusa , M. Salvato , C. Laigle , H. J. McCracken , O. Ilbert

The aim of this paper is to revisit critically the current census of AGN as derived from optical spectroscopy. We considered the spectra of nearby (z<0.1) galaxies from the Sloan Digital Sky Survey (SDSS). The equivalent width (EW)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Alessandro Capetti

(Abridged) We present an unbiassed near-IR selected AGN sample, covering 12.56 square degrees down to K ~ 15.5, selected from the Two Micron All Sky Survey (2MASS). Our only selection effect is a moderate color cut (J-K>1.2) designed to…

Astrophysics · Physics 2009-11-10 Paul J Francis , Brant O. Nelson , Roc M. Cutri

This study aims to explore the relation between dwarf galaxies ($M_* \leq 5\times10^9 M_\odot$) with AGNs and their environment by comparing neighbourhood parameters of AGN and non-AGN samples. Using the NASA-Sloan Atlas, both the local…

Astrophysics of Galaxies · Physics 2020-06-16 Mikkel T. Kristensen , Kevin Pimbblet , Samantha Penny

The joint catalogue of Active Galactic Nuclei selected from optical identifications of X-ray sources was created as a combination of two samples: Hamburg-ROSAT Catalogue (HRC) and Byurakan-Hamburg-ROSAT Catalogue (BHRC). Both are based on…

Astrophysics of Galaxies · Physics 2015-11-24 A. M. Mickaelian , G. M. Paronyan , G. S. Harutyunyan , H. V. Abrahamyan , M. V. Gyulzadyan

We investigate the radio emission of ~185,000 quiescent (optically unclassifiable) galaxies selected from the Sloan Digital Sky Survey (SDSS). By median-stacking FIRST cutouts centered on the optically-selected sources, we are able to reach…

Astrophysics · Physics 2009-11-13 J. A. Hodge , R. H. Becker , R. L. White , W. H. de Vries

Radio-emitting jets might be one of the main ingredients shaping the evolution of massive galaxies in the Universe since early cosmic times. However, identifying early radio active galactic nuclei (AGN) and confirming this scenario has been…

‹ Prev 1 4 5 6 7 8 10 Next ›