Results 1 to 10 of about 977,708 (130)
Why Are Some Radio Galaxies Detected by Fermi, but Others Not?
Universe, 2023 Aiming to answer an interesting question on why some radio sources can be detected by Fermi-LAT but others cannot, we compare several parameters of Fermi-detected Fanaroff-Riley radio galaxies (FFRs) and non-Fermi-detected sources (NFFRs), including the ...
Danyi Huang +11 more
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Accretion mode and jet collimation in active galactic nuclei
Astronomische Nachrichten, Volume 342, Issue 9-10, Page 1071-1076, November-December 2021., 2021 Abstract In this article, we summarize our recent progress in observational studies of jet collimation in active galactic nuclei. We focus on the investigation of a relation between the properties of the collimation zone and the AGN accretion mode, recently proposed by Boccardi, B., Perucho, M., Casadio, C. et al., 2021, A&A, 647, A67.
Bia Boccardi +2 more
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Hunting Gamma-Ray-emitting FR0 Radio Galaxies in Wide-field Sky Surveys
The Astrophysical Journal, 2023 The latest entry in the jetted active galactic nuclei (AGN) family is the Fanaroff–Riley type 0 (FR0) radio galaxies. They share several observational characteristics, e.g., nuclear emission and host galaxy morphology, with FR I sources; however, they ...
Meghana Pannikkote +2 more
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Combining LOFAR and Apertif Data for Understanding the Life Cycle of Radio Galaxies
Galaxies, 2021 Active galactic nuclei (AGN) at the centres of galaxies can cycle between periods of activity and of quiescence. Characterising the duty-cycle of AGN is crucial for understanding their impact on the evolution of the host galaxy.
Raffaella Morganti +12 more
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Morphological-based Analyses for Parameterizing Symmetry in Radio Galaxies
The Astronomical Journal, 2023 The morphology of radio galaxies can provide significant clues to describe the formation and evolution of galaxies in the Universe. Here, we aim to extract the morphological parameters of radio galaxies and define symmetry criteria as some of the ...
Mohsen Javaherian +2 more
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Research on Morphological Detection of FR I and FR II Radio Galaxies Based on Improved YOLOv5
Universe, 2021 Recently, astronomy has witnessed great advancements in detectors and telescopes. Imaging data collected by these instruments are organized into very large datasets that form data-oriented astronomy.
Xingzhu Wang +6 more
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A Quick Look at the 3 GHz Radio Sky. II. Hunting for DRAGNs in the VLA Sky Survey
The Astrophysical Journal Supplement Series, 2023 Active galactic nuclei (AGNs) can often be identified in radio images as two lobes, sometimes connected to a core by a radio jet. This multicomponent morphology unfortunately creates difficulties for source finders, leading to components that are (a ...
Yjan A. Gordon +11 more
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Direct HST Dust Lane Detection in Powerful Narrow-Line Radio Galaxies
Frontiers in Astronomy and Space Sciences, 2017 We present the analysis of near-infrared Hubble Space Telescope imaging of 10 Fanaroff Riley II powerful radio galaxies at low redshift (0.03 < z < 0.11) optically classified as narrow-line radio galaxies.
Edgar A. Ramírez +7 more
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On the Subparsec-scale Core Composition of FR 0 Radio Galaxies
The Astrophysical Journal Letters, 2023 Although Fanaroff–Riley type 0 (FR 0) radio galaxies are known to be the most numerous jet population in the local Universe, they are much less explored than the well-established class of FR type I (FR I) and FR type II galaxies due to their intrinsic ...
Margot Boughelilba, Anita Reimer
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The Era of Kilometer‐Scale Neutrino Detectors
Advances in High Energy Physics, Volume 2013, Issue 1, 2013., 2013 Neutrino astronomy beyond the Sun was first imagined in the late 1950s; by the 1970s, it was realized that kilometer‐scale neutrino detectors were required. The first such instrument, IceCube, transforms a cubic kilometer of deep and ultra‐transparent Antarctic ice into a particle detector.
Francis Halzen, Uli Katz, Jose Bernabeu
wiley +1 more source