Related papers: Broad-line Active Galactic Nuclei in the 6dF Galax…

X-rays offer a reliable method to identify Active Galactic Nuclei (AGN). However, in the high-redshift Universe X-ray AGN are poorly sampled due to their relatively low space density and the small areas covered by X-ray surveys. In addition…

(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…

Using Spitzer-IRS spectroscopy, we investigate the ubiquity of Active Galactic Nuclei (AGN) in a complete (~94%), volume-limited sample of the most bolometrically-luminous galaxies (L_IR > (0.3-20) x 10^10 L_sun) to D < 15 Mpc. Our analyses…

We present a sample of 47 confirmed and 14 candidate Active Galactic Nuclei (AGN) discovered in the Canadian Network for Observational Cosmology field galaxy redshift survey (CNOC2). The sample consists of 38 objects identified from broad…

We present the results of our search for highly variable active galactic nuclei (AGNs) the X-ray flux from which changed by more than an order of magnitude during the SRG/eROSITA all-sky survey. Using the eROSITA data obtained in the period…

Active galactic nuclei (AGNs) in the high-redshift Universe are thought to reside in overdense environments. However, recent works provide controversial results partly due to the use of different techniques and possible suppression of…

The spectra of Active Galactic Nuclei (AGNs) are often characterized by a wealth of emission lines with different profiles and intensity ratios that led to a complicated classification. Their electro-magnetic radiation spans more than 10…

We present the results of a 2-epoch variability survey in the Hubble Deep Field with the goal of investigating the population of AGN to z=1. The primary data sets analyzed for galactic variability are the original HDF observations obtained…

We present the first quantified, statistical map of broad-line active galactic nucleus (AGN) frequency with host galaxy color and stellar mass in nearby (0.01 < z < 0.11) galaxies. Aperture photometry and z-band concentration measurements…

We present the first results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a cross-correlation of the ROSAT All Sky Survey (RASS) bright…

We report the final redshift release of the 6dF Galaxy Survey, a combined redshift and peculiar velocity survey over the southern sky (|b|>10 deg). Its 136,304 spectra have yielded 110,256 new extragalactic redshifts and a new catalogue of…

We present a catalog of 510 radio-loud active galactic nuclei (AGN, primarily blazars) and 287 dusty star-forming galaxies (DSFGs) detected by the Atacama Cosmology Telescope at $>5\sigma$ significance in bands centered on 148 GHz (2 mm),…

We present spectral energy distributions (SEDs) of 41 active galactic nuclei, derived from multiwavelength photometry and archival spectroscopy. All of the SEDs span at least 0.09 to 30 micron, but in some instances wavelength coverage…

We have completed a spectroscopic survey of X-ray point sources in eight low-redshift clusters of galaxies (0.05<z<0.31) and have identified 40 cluster members with broad-band (0.3-8 keV) X-ray luminosities between L_X = 8x10^{40} and…

In this work we have updated the list of AGN detected by INTEGRAL taking into account the new objects listed in the last published INTEGRAL/IBIS survey. We have collected 83 new AGN increasing the number of INTEGRAL detected active galaxies…

We present a 19.7 - 214 $\mu$m imaging atlas of local (4 - 181 Mpc; median 43 Mpc) active galactic nuclei (AGN) observed with FORCAST and HAWC+ on board the SOFIA telescope with angular resolutions ~ 3"- 20". This atlas comprises 22…

The third catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (3LAC) is presented. It is based on the third catalog (3FGL,\cite{3FGL}) of sources detected with a test statistic greater than 25, using the…

We present 71 Emission Line objects selected from the REX survey. Except for 3 of them, for which the presence of an active nucleus is dubious, all these sources are Active Galactic Nuclei (QSOs, Seyfert galaxies, emission line…

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…

A global understanding of Active Galactic Nuclei (AGN) and their host galaxies hinges on completing a census of AGN activity without selection biases down to the low-luminosity regime. Toward that goal, we identify AGN within faint radio…