Results 71 to 80 of about 77,605 (280)
The Astrophysical Journal Supplement SeriesWe present the active galactic nuclei (AGN) catalog from the fourth data release (HDR4) of the Hobby–Eberly Telescope Dark Energy Experiment Survey (HETDEX). HETDEX is an untargeted spectroscopic survey.
Chenxu Liu +9 more
doaj +1 more source
X-Ray Unveiling Events in a z ≈ 1.6 Active Galactic Nucleus in the 7 Ms Chandra Deep Field-South
The Astrophysical Journal, 2023 We investigate the extreme X-ray variability of a z = 1.608 active galactic nucleus in the 7 Ms Chandra Deep Field-South (XID 403), which showed two significant X-ray brightening events.
Li-Ming Yu +16 more
doaj +1 more source
Infrared spectroscopic diagnostics for Active Galactic Nuclei
, 2007 Infrared spectroscopy in the mid- and far-infrared provides powerful diagnostics for studying the emission regions in active galaxies. The large variety of ionic fine structure lines can probe gas conditions in a variety of physical conditions, from ...
Spinoglio, Luigi
core +1 more source
Intermediate-mass Black Holes in Galactic Nuclei [PDF]
, 2004 We present the first homogeneous sample of intermediate-mass black hole candidates in active galactic nuclei. Starting with broad-line active nuclei from the Sloan Digital Sky Survey, we use the linewidth-luminosity-mass scaling relation to select a ...
Barth, A. J., Greene, J. E., Ho, L. C.
core +3 more sources
The Promise and Pitfalls of Artificial Intelligence in the Evaluation of Synthetic “Greenness”
ChemSusChem, EarlyView.Rapid rise of AI prompts a question whether it can be used to accelerate and standardize assessment of synthetic “greenness.” This perspective argues for the potential of such applications, although it also identifies several hurdles, like the need for extensive training or the creation of “ground truth” datasets.
Paweł Mateusz Nowak +3 more
wiley +1 more source
The incidence of obscuration in active galactic nuclei [PDF]
Monthly Notices of the Royal Astronomical Society, 2013 We study the incidence of nuclear obscuration on a complete sample of 1310 AGN selected on the basis of their rest-frame 2-10 keV X-ray flux from the XMM-COSMOS survey, in the redshift range 0 ...
Vincenzo Mainieri +26 more
openaire +6 more sources
LINERs as Low-Luminosity Active Galactic Nuclei
, 1998 Many nearby galaxies contain optical signatures of nuclear activity in the form of LINER nuclei. LINERs may be the weakest and most common manifestation of the quasar phenomenon.
Antonucci +44 more
core +2 more sources
Effect of Background Magnetic Field on Ion Weibel Instability With High‐Intensity Short‐Pulse Lasers
Contributions to Plasma Physics, EarlyView.ABSTRACT The effect of finite background magnetic field on magnetic field amplification by Weibel instability using high‐intensity short‐pulse lasers is investigated. We consider Weibel instability for counter‐streaming sub‐relativistic plasma flows generated by shooting pure carbon targets with short‐pulse lasers.
Taiki Jikei +3 more
wiley +1 more source
The Astrophysical Journal LettersRecent James Webb Space Telescope observations have revealed a population of compact extragalactic objects at z ≳ 4 with red near-infrared colors, which have been dubbed as “Little Red Dots” (LRDs).
Minghao Yue +5 more
doaj +1 more source
X-ray Eclipses of Active Galactic Nuclei
, 2017 X-ray variation is a ubiquitous feature of active galactic nuclei (AGNs), however, its origin is not well understood. In this paper, we show that the X-ray flux variations in some AGNs, and correspondingly the power spectral densities (PSDs) of the ...
Lu, Youjun, Yu, Qingjuan, Zhang, Fupeng
core +1 more source