Results 1 to 10 of about 116 (115)
Properties of Very Broad Line MgII Radio-Loud and Radio-Quiet Quasars
Galaxies, 2021 We perform an analysis of the properties of radio-loud (RL) and radio-quiet (RQ) quasars with MgII broad emission line (i-band magnitude ≤19.1 and z ≤1.9), selected from the parent sample of SDSS DR7 catalogue.
Avinanda Chakraborty +2 more
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The Origin and Evolution of Giant Radio Galaxies
Frontiers in Astronomy and Space Sciences, 2022 Giant radio galaxies are arguably the least understood of jetted active galactic nuclei (AGN). We propose that radio galaxies are the product of large mergers that do not involve radio galaxies or radio quasars, such as in merging spiral galaxies, while ...
David Garofalo
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The Nature of the IMBH Candidate CXO J133815.6+043255: High-frequency Radio Emission
The Astrophysical Journal, 2023 The ultraluminous X-ray source CXO J133815.6+043255 is a strong candidate for a bona fide intermediate-mass black hole residing in the outskirts of NGC 5252.
Krista Lynne Smith +2 more
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How Are Red and Blue Quasars Different? The Radio Properties
Galaxies, 2021 A non-negligible fraction of quasars are red at optical wavelengths, indicating (in the majority of cases) that the accretion disc is obscured by a column of dust which extinguishes the shorter-wavelength blue emission. In this paper, we summarize recent
Victoria A. Fawcett +3 more
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Extreme accretion events: TDEs and changing‐look AGN
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract We present a review of the topics of X‐ray stellar tidal disruption events (TDEs) and changing‐look active galactic nuclei (AGN). Stars approaching a supermassive black hole (SMBH) can be tidally disrupted and accreted. TDEs were first discovered in the X‐ray regime and appear as luminous, giant‐amplitude flares from inactive galaxies.
S. Komossa, D. Grupe
wiley +1 more source
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract The non‐linear correlation between the UV and X‐ray emission observed in active galactic nuclei remains a puzzling question that challenges accretion models. While the UV emission originates from the cold disk, the X‐ray emission is emitted by a hot corona whose physical characteristics and geometry are still highly debated.
S. Barnier +3 more
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The road toward imaging a black hole: A personal perspective
Natural Sciences, Volume 2, Issue 4, October 2022., 2022 The article describes the authors personal journey towards developig the Event Horizon Telescope and the first image of a black hole. Left: predcition made by the author and collaborators proposing the black hole imaging in 2000. Right: the two images observed and published by the Event Horizon Telescope in 2019 and 2022.
Heino Falcke
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Metal Content in Relativistically Jetted and Radio-Quiet Quasars in the Main Sequence Context
Galaxies, 2023 The optical and UV properties of radio-quiet (RQ) and radio-loud (RL, relativistically “jetted”) active galactic nuclei (AGN) are known to differ markedly; however, it is still unclear what is due to a sample selection and what is associated with ...
Paola Marziani +3 more
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The Astrophysical Journal, 2023 We present polarization-sensitive images from the Karl G. Jansky Very Large Array (VLA) at 5 GHz of 11 radio-quiet PG quasars. Based on the radio morphology, spectral index, and polarization properties from the VLA study, coupled with the findings of our
Silpa S. +3 more
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Phylogenetic Analyses of Quasars and Galaxies
Frontiers in Astronomy and Space Sciences, 2017 Phylogenetic approaches have proven to be useful in astrophysics. We have recently published a Maximum Parsimony (or cladistics) analysis on two samples of 215 and 85 low-z quasars (z < 0.7) which offer a satisfactory coverage of the Eigenvector 1 ...
Didier Fraix-Burnet +2 more
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