Results 111 to 120 of about 22,530 (230)
The Astrophysical JournalWe present here the results from a second epoch of phase-referenced VLBA observations of eight Seyfert and LINER galaxies from the KISSR sample. These sources were chosen based on the presence of double peaks or asymmetries in their emission lines as ...
Preeti Kharb +6 more
doaj +1 more source
Free-Free Absorption and the Unified Scheme [PDF]
, 2003 We report Very-Long-Baseline Array (VLBA) observations at 2.3, 8.4, and 15.4 GHz towards nine GHz-Peaked Spectrum (GPS) sources. One Seyfert 1 galaxy, one Seyfert 2 galaxy, three radio galaxies, and four quasars were included in our survey.
Carvalho +9 more
core +3 more sources
Narrow-Line Seyfert 1 Galaxies
, 2007 To appear in the proceedings of "The nuclear region, host galaxy and environment of AGN", E. Benitez, I. Cruz-Gonzalez & Y.
openaire +3 more sources
COMPTEL upper limits for Seyfert galaxies
AIP Conference Proceedings, 1994 The gamma‐ray emission of Seyfert galaxies has fallen far short of pre‐GRO expectations. No single object of this class has been detected by either COMPTEL or EGRET, and OSSE has detected only a fraction of the Seyferts expected. To derive a more stringent upper limit to the emission from these objects in the energy ranges 0.75 to 1 and 1 to 3 MeV, we ...
Maisack, M +10 more
openaire +4 more sources
Compact Radio Sources and Nuclear Activity in Seyfert Galaxies [PDF]
, 1996 Using recent high-resolution radio observations of a large sample of Seyfert galaxies (Roy et al. 1994), we analyze the relations between the compact radio core emission and several nuclear and host galaxy properties.
Fadda, Dario +2 more
core +3 more sources
Modeling Star Formation Histories of Changing-look AGN Host Galaxies with Prospector
The Astrophysical JournalChanging-look active galactic nuclei (CL-AGNs), are AGNs that appear to transition between Seyfert Type 1 and 2 over periods of months to years. Several mechanisms to trigger these transitions have been proposed, but we have yet to conclusively determine
Margaret E. Verrico +9 more
doaj +1 more source
A Panchromatic View of Relativistic Jets in Narrow-Line Seyfert 1 Galaxies
Galaxies, 2016 The discovery by the Large Area Telescope on board Fermi of variable γ-ray emission from radio-loud narrow-line Seyfert 1 (NLSy1) galaxies revealed the presence of a possible third class of Active Galactic Nuclei (AGN) with relativistic jets in addition ...
Filippo D’Ammando +5 more
doaj +1 more source
The Central Kiloparsec of Seyfert and Inactive Host Galaxies: a Comparison of Two-Dimensional Stellar and Gaseous Kinematics [PDF]
, 2007 We investigate the properties of the two-dimensional distribution and kinematics of ionised gas and stars in the central kiloparsecs of a matched sample of nearby active (Seyfert) and inactive galaxies, using the SAURON Integral Field Unit on the William
Dumas, Gaelle +3 more
core +5 more sources
The hard X-ray view of bright infrared galaxies
, 2009 Aims. The synthesis of the cosmic X-ray background (CXB) requires a large population of Compton-thick active galactic nuclei that have not been detected so far.
Akylas +39 more
core +1 more source
Intensive Broadband Reverberation Mapping of Fairall 9 with 1.8 yr of Daily Swift Monitoring
The Astrophysical JournalWe present 1.8 yr of near-daily Swift monitoring of the bright, strongly variable Type 1 active galactic nucleus (AGN) Fairall 9. Totaling 575 successful visits, this is the largest such campaign reported to date.
R. Edelson +7 more
doaj +1 more source