Results 131 to 140 of about 4,973 (222)
Revealing two radio-active galactic nuclei extremely near PSR J0437−4715
, 2018 Newton\u27s gravitational constant G may vary with time at an extremely low level. The time variability of G will affect the orbital motion of a millisecond pulsar in a binary system and cause a tiny difference between the orbital period-dependent ...
Paragi, Zsolt +35 more
core +2 more sources
Deciphering Radio Emissions from Accretion Disk Winds in Radio-quiet Active Galactic Nuclei
The Astrophysical JournalUnraveling the origins of radio emissions from radio-quiet active galactic nuclei (RQ AGNs) remains a pivotal challenge in astrophysics. One potential source of this radiation is the shock interaction between AGN disk winds and the interstellar medium ...
Tomoya Yamada +3 more
doaj +1 more source
The Astrophysical JournalBased on the magnetization, an accretion disk with a large-scale magnetic field can be separated into either standard and normal evolution or magnetically arrested disk (MAD), which are difficult to identify from observations. It is still unclear whether
Shuang-Liang Li, Wenwen Zuo, Xinwu Cao
doaj +1 more source
RAiSERed: radio continuum redshifts for lobed active galactic nuclei
, 2020 Next-generation radio surveys are expected to detect tens of millions of active galactic nuclei (AGNs) with a median redshift of ≥ 1. Beyond targeted surveys, the vast majority of these objects will not have spectroscopic redshifts, while photometric ...
Seymour, N (15552026) +3 more
core
Theoretical Models of Active Galactic Nuclei [PDF]
, 1984 We review attempts to incorporate radio sources within the context of general models of active galactic nuclei. The behaviour of gas accreting onto a massive black hole depends upon its angular momentum and accretion rate.
Blandford, R. D.
core
Constraining Star Formation in M87 Using Deep Hubble Space Telescope UV Data
The Astrophysical JournalWe analyzed the deepest Hubble Space Telescope F275W ultraviolet (UV) imaging of M87 to obtain the most robust constraints on its star formation rate (SFR) and star formation history (SFH).
Prathamesh Tamhane +13 more
doaj +1 more source
Are the jets accelerated from the disk coronas in some active galactic nuclei?
, 2004 We use a sample of radio-loud active galactic nuclei (AGNs) with estimated central black hole masses to explore AGN jet-formation mechanisms. The jet power of AGNs is estimated from their extended radio luminosity.
Cao, XW
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WHAT GOVERNS THE BULK VELOCITY OF THE JET COMPONENTS IN ACTIVE GALACTIC NUCLEI?
, 2012 We use a sample of radio-loud active galactic nuclei (AGNs) with measured black hole masses to explore the jet formation mechanisms in these sources. Based on Konigl's inhomogeneous jet model, the jet parameters, such as the bulk motion Lorentz factor ...
Chai, Bo, Cao, Xinwu, Gu, Minfeng
core
Revisiting Radio Variability of the Blazar 3C 454.3
The Astrophysical JournalWe examine lengthy radio light curves of the flat spectrum radio galaxy 3C 454.3 for possible quasiperiodic oscillations (QPOs). The data used in this work were collected at five radio frequencies, 4.8, 8.0, 14.5, 22.0, and 37.0 GHz between 1979 and 2013
Ashutosh Tripathi +9 more
doaj +1 more source
Long-term radio variability of active galactic nuclei at 37 GHz
Aims. We present the results of analysing the long-term radio variability of active galactic nuclei at 37 GHz using data of 123 sources observed in the Aalto University Metsähovi Radio Observatory.
Tornikoski, Merja +7 more
core +1 more source