1,407 datasets found

Variability is a ubiquitous feature of active galactic nuclei (AGNs), and the characterisation of the variability is crucial to constrain its physical mechanism and proper...

Blazars are the most common sources of gamma-ray photons in the extra-galactic sky. Their gamma-ray light-curves are characterized by bright flaring episodes, similarly to what...

Some Active Galactic Nuclei (AGN) host outflows which have the potential to alter the host galaxy's evolution (AGN feedback). These outflows have been linked to enhanced radio...

As an inaugural investigation under the X-ray Winds In Nearby-to-distant Galaxies (X-WING) program, we assembled a data set comprising 132 active galactic nuclei (AGNs) spanning...

We present the results of deep observations of the Lockman Hole field with the ASCA SIS, covering 926arcmin^2^ in the 1-7keV energy range, with a sensitivity 3-5 times deeper...

The VSOP mission is a Japanese-led project to image radio sources with sub-milliarcsec resolution by correlating the signal from the orbiting 8-m telescope, HALCA, with a global...

We considered the fourth catalog of gamma-ray point sources produced by the Fermi Large Area Telescope (LAT) and selected only jetted active galactic nuclei (AGN) or sources...

Accretion disks around supermassive black holes in active galactic nuclei produce continuum radiation at ultraviolet and optical wavelengths. Physical processes in the accretion...

Black holes generate collimated, relativistic jets, which have been observed in {gamma}-ray bursts (GRBs), microquasars, and at the center of some galaxies [active galactic...

We study the correlation between the emission from the broad-line region (BLR) and the emission in other wavelength ranges (from radio to x-ray) for the sample of 37 blazars (25...

The results of a comprehensive analysis of continuous radio spectra of a sample of Gigahertz-Peaked Spectrum (GPS) sources are reported. The sources are selected from a...

We observed 51 sources in the Q-U-I JOint TEnerife (QUIJOTE) cosmological fields which were brighter than 1Jy at 30GHz in the Planck Point Source Catalogue (version 1), with the...

Using a sample of 208 broad-line active galactic nuclei (AGNs) from the Swift/BAT AGN Spectroscopic Survey in the ultra-hard X-ray band (14-195keV), the hot corona properties...

We analyse 2015 mid-infrared (MIR) spectra of galaxies observed with Spitzer's Infrared Spectrograph, including objects with growing supermassive black holes (SMBHs) and objects...

We investigate broad absorption line (BAL) disappearance and emergence using a 470 BAL-quasar sample over <=0.10-5.25 rest-frame years with at least three spectroscopic...

We obtained new quantitative determinations of the nitrogen abundance and a consistent relation between the nitrogen and oxygen abundances for a sample of Seyfert 2 galaxies...

Stars form in cold molecular clouds. However, molecular gas is difficult to observe because the most abundant molecule (H_2_) lacks a permanent dipole moment. Rotational...

A large fraction of active galactic nuclei (AGN) are 'invisible' in extant optical surveys due to either distance or dust-obscuration. The existence of this large population of...

We have cross matched the Gaia Data Release 1 secondary data set that contains positions of 1.14 billion objects against the most complete to date catalogue of very long...

We provide a comprehensive census of the near-infrared (NIR, 0.8-2.4um) spectroscopic properties of 102 nearby (z<0.075) active galactic nuclei (AGN), selected in the hard...