Results 31 to 40 of about 4,320,326 (297)
Nuclear activity in isolated galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2013 7 figures, 7 ...
Francisco J. Hernández-Ibarra +5 more
openaire +3 more sources
FAR-INFRARED LINE SPECTRA OF ACTIVE GALAXIES FROM THE HERSCHEL/PACS SPECTROMETER: THE COMPLETE DATABASE [PDF]
, 2016 We present a coherent database of spectroscopic observations of far-IR fine-structure lines from the Herschel/Photoconductor Array Camera and Spectrometer archive for a sample of 170 local active galactic nuclei (AGNs), plus a comparison sample of 20 ...
J. Fernández-Ontiveros +5 more
semanticscholar +1 more source
The Astrophysical Journal Supplement Series, 2023 The main objective of this article, the first in a dedicated series, is to report basic results on systematic research of low-redshift optically selected SDSS Type 2 active galactic nuclei (AGNs) but with apparent optical variabilities.
XueGuang Zhang
doaj +1 more source
BROAD Hβ EMISSION-LINE VARIABILITY IN A SAMPLE OF 102 LOCAL ACTIVE GALAXIES [PDF]
, 2016 A sample of 102 local (0.02 ≤ z ≤ 0.1) Seyfert galaxies with black hole masses MBH > 107M⊙ was selected from the Sloan Digital Sky Survey (SDSS) and observed using the Keck 10 m telescope to study the scaling relations between MBH and host galaxy ...
Jordan N. Runco +9 more
semanticscholar +1 more source
Statistical Properties of Radio Emission from the Palomar Seyfert Galaxies [PDF]
, 2001 We have carried out an analysis of the radio and optical properties of a statistical sample of 45 Seyfert galaxies from the Palomar spectroscopic survey of nearby galaxies.
Antonucci R. R. J. +15 more
core +2 more sources
Spectral properties of AGN with very weak [O III] lines [PDF]
Serbian Astronomical Journal, 2011 The spectral properties of a sample of 58 Active Galactic Nuclei (AGN) spectra, in which emission [O III] λλ4959, 5007 Å lines are weak or totally absent, are analyzed.
Kovačević J.
doaj +3 more sources
The distribution and lifetime of powerful radio galaxies as a function of environment and redshift
Scientific Reports, 2018 Correlations between jet power and active time for z
David Garofalo +2 more
doaj +1 more source
Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships [PDF]
, 2002 We present four improved empirical relationships useful for estimating the central black hole mass in nearby AGNs and distant luminous quasars alike using either optical or UV single-epoch spectroscopy.
M. Vestergaard, B. Peterson
semanticscholar +1 more source
The Origin and Evolution of Giant Radio Galaxies
Frontiers in Astronomy and Space Sciences, 2022 Giant radio galaxies are arguably the least understood of jetted active galactic nuclei (AGN). We propose that radio galaxies are the product of large mergers that do not involve radio galaxies or radio quasars, such as in merging spiral galaxies, while ...
David Garofalo
doaj +1 more source
Identification of active galaxies behind the Coma cluster of galaxies [PDF]
Astronomy and Astrophysics Supplement Series, 1999 We describe the results of an efficient survey to identify bright B < ∼ 18 active galactic nuclei (AGN) within ≈ 4 • (4.7 h −1 Mpc projected radius) of the centre of the Coma cluster of galaxies. The candidates have been carefully selected either as unresolved UV-excess objects with no detected proper motion, or from identifications on objective-prism ...
Ledoux, C +5 more
openaire +3 more sources