Results 101 to 110 of about 152,801 (176)

The Host Galaxy Fluxes of Active Galaxy Nuclei Are Generally Overestimated by the Flux Variation Gradient Method

Universe
In terms of the variable nature of normal active galaxy nuclei (AGN) and luminous quasars, a so-called flux variation gradient (FVG) method has been widely utilized to estimate the underlying non-variable host galaxy fluxes.
Minxuan Cai, Zhen Wan, Zhenyi Cai, Lulu Fan, Junxian Wang   +4 more
doaj   +1 more source

SPECTRAL AND PHOTOMETRIC STUDIES OF MRK6 AND MRK1040 IN THE OPTICAL RANGE

Eurasian Physical Technical Journal
This paper is dedicated to the study of variability in active galactic nuclei, which play a key role in understanding the physical processes occurring in their central regions.
S.A. Shomshekova, E.K. Denissyuk, L.N. Kondratyeva, A.V. Serebryanskiy, G.K. Aimanova, L. Aktay   +5 more
doaj   +1 more source

Anomalous Narrow Line Seyfert I Galaxies from SDSS DR17

The Astrophysical Journal
We present an analysis of 22,656 narrow-line Seyfert 1 galaxies (NLSy1s) from the Sloan Digital Sky Survey (SDSS) DR17 (0.1 ≤ z ≤ 0.9), identifying a sample of spectroscopically anomalous sources.
Arihant Tiwari, Rachana, M. Vivek, Suvendu Rakshit   +3 more
doaj   +1 more source

The Faber-Jackson relation in Seyfert galaxies

, 2007
Seyfert galaxies, in which accretion onto a massive nuclear black hole acts as a powerful energy source, allegedly have bulges more luminous per unit mass than those in normal galaxies.
Weinzirl, Timothy, Madland, Mark, Bennett, Wendy   +2 more
core  

The SRG/eROSITA all-sky survey: Hard X-ray selected active galactic nuclei

Astronomy & Astrophysics
Context. The eROSITA instrument on board the Spectrum Roentgen Gamma (SRG) satellite performed its first all-sky survey between December 2019 and June 2020.
Waddell S. G. H., Buchner J., Nandra K., Salvato M., Merloni A., Gauger I., Boller Th., Seppi R., Wolf J., Liu T., Brusa M., Comparat J., Dwelly T., Igo Z., Musiimenta B.   +14 more
doaj   +1 more source

Soft X-ray properties of a spectroscopically selected sample of interacting and isolated Seyfert galaxies

, 2001
We present a catalogue of ROSAT detected sources in the sample of spectroscopically selected Seyfert 1 and Seyfert 2 galaxies of Rafanelli et al. (\cite{Rafanelli95}). The catalogue contains 102 Seyfert 1 and 36 Seyfert 2 galaxies.
P. Rafanelli, F. Pfefferkorn, PFEFFERKORN F., Th. Boller, RAFANELLI, PIERO, BOLLER T.H.   +5 more
core   +1 more source

Are “Changing-look” Active Galactic Nuclei Special in the Coevolution of Supermassive Black Holes and their Hosts? II. The Case of Changing-look Narrow-line Seyfert 1 Galaxies

The Astrophysical Journal
The evolutionary role of the so-called “changing-look” (CL) active galactic nucleus (AGN), which is characterized by spectral-type transitions within ∼10 yr, has been suggested in the past few years. By focusing on CL-AGNs having spectra similar to those
J. Wang, S. Jin, D. W. Xu, WeiKang Zheng, Thomas G. Brink, S. Komossa, Alexei V. Filippenko, J. Y. Wei   +7 more
doaj   +1 more source

A Systematic Study of the Long-term Mid-infrared Color Variations of Seyfert 1 Galaxies

The Astrophysical Journal Supplement Series
We present a comparative analysis of long-term mid-infrared (MIR) color variations (MCVs) for 1977 narrow-line Seyfert 1 (NLSy1) and 4113 broad-line Seyfert 1 (BLSy1) galaxies at z  
Jiahua Wu, Liming Dou, Zhining Chen, Fupeng Zhang, Luis C. Ho, Yanli Ai, Tinggui Wang, Xinwen Shu, Ning Jiang, Junfeng Wang   +9 more
doaj   +1 more source

Galactic outflows and star-formation quenching: a JWST perspective. [PDF]

Astrophys Space Sci
Davies RL, Belli S.
europepmc   +1 more source

Galaxy Evolution with Manifold Learning. [PDF]

Entropy (Basel)
Takeuchi TT, Cooray S, Kano RR.
europepmc   +1 more source