Results 101 to 110 of about 3,447,628 (240)
New Insight from the James Webb Space Telescope on Variable Active Galactic Nuclei
The Astrophysical JournalVariability detected in galaxies is usually attributed to their active galactic nuclei (AGNs). While all AGNs are intrinsically variable, the AGN unification model predicts that Type 2 AGNs rarely vary because their engines are blocked by dust tori ...
Bangzheng Sun +3 more
doaj +1 more source
A Metric for Quantifying Spatial Heterogeneity in Gridded Atmospheric Fields
Earth and Space Science, Volume 13, Issue 9, September 2026.Abstract Spatial heterogeneity influences many nonlinear atmospheric processes but it is often described qualitatively or with simple statistical measures that do not capture spatial organization. We introduce a mixing‐oriented metric for gridded fields based on the expected deviation of subdomain means from the global average.
M. Mohebalhojeh +3 more
wiley +1 more source
DUST IN ACTIVE GALACTIC NUCLEI: ANOMALOUS SILICATE TO OPTICAL EXTINCTION RATIOS?
, 2014 Dust plays a central role in the unification theory of active galactic nuclei (AGNs). However, little is known about the nature (e.g., size, composition) of the dust that forms a torus around the AGN. In this Letter, we report a systematic exploration of
Lyu, Jianwei, Hao, Lei, Li, Aigen
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Breaking the σ₈–Ωₘ degeneracy using the clustering of HIGH- x-ray active galactic nuclei [PDF]
, 2010 The clustering of X-ray selected active galactic nuclei (AGNs) appears to be a valuable tool for extracting cosmological information. Using the recent high-precision angular clustering results of ∼30,000 XMM-Newton soft (0.5–2 keV) X-ray sources, which ...
Manolis Plionis
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Dual Active Galactic Nuclei on 100 kpc Scales from the Million Quasar Catalog
The Astrophysical Journal Supplement SeriesResearch on dual active galactic nuclei (AGNs) is crucial for understanding the coevolution of galaxies and supermassive black holes. However, the current number of dual AGNs remains scarce. In this work, we selected 171 new dual AGNs, four AGN triplets,
Zhuojun Deng +5 more
doaj +1 more source
Journal of Geophysical Research: Planets, Volume 131, Issue 9, September 2026.Abstract In this work we investigate how ionization from Galactic Cosmic Rays (GCRs) can affect aerosol nucleation on Neptune and discuss potential implications for the observed brightness variations that appear to follow the solar cycle. We calculate the planetary vertical cutoff rigidity for Neptune based on the O8 ${\mathrm{O}}_{8}$ magnetic field ...
Martin B. B. Enghoff +3 more
wiley +1 more source
X-ray and UV emission from active galactic nuclei
, 1984 SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische ...
Truemper, J. (eds.) +2 more
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Compact objects in active galactic nuclei and X-ray binaries [PDF]
, 2007 In this thesis I study the inner-most regions of Active Galactic Nuclei (AGN) using the reverberation mapping technique, and neutron star low-mass X-ray binaries in quiescence using X-ray observations. Using the 13-year optical monitoring data for the
Cackett, Edward M.
core +2 more sources
Time-domain Radio-loudness of Active Galactic Nuclei: Intermittency, Memory, and Jet Escape
The Astrophysical Journal LettersThe classical radio-loudness parameter R ≡ f _ν (5 GHz)/ f _ν (4400 Å) divides a radio flux density by an optical/UV accretion tracer, but the two terms do not probe the same clock.
Tao An
doaj +1 more source
Ferric Chloride: The Venusian Unknown UV Absorber?
Journal of Geophysical Research: Planets, Volume 131, Issue 9, September 2026.Abstract Near‐ultraviolet imaging of the planet Venus reveals inhomogeneous absorption features in the otherwise bright clouds. This absorption has been studied for nearly 100 years, but identification of the near‐UV absorber remains one of the largest open questions in Venusian research.
Joanna V. Egan +8 more
wiley +1 more source