Results 161 to 170 of about 352 (180)

Water megamasers as a probe of a circumnuclear accretion disk in an active galaxy

Symposium - International Astronomical Union, 1997
In the past three years, observations of extragalactic water masers have demonstrated the extraordinary power of spectral line radio interferometry to probe the inner regions of active galaxies on subparsec scales. In the case of the active galaxy NGC 4258, the observations of Miyoshi et al.
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Accretion of gaseous disks of galaxies. II. Allowance for viscosity in a disk consisting of giant molecular clouds

Astrophysics, 1987
The evolution of the distribution of giant molecular clouds in galaxies under the influence of dynamical friction on stars and viscosity is calculated in the approximation of a collisionless gas. It is shown that in principle the joint action of the viscosity and the dynamical friction can lead to the formation of the ring-shaped distribution of giant ...
O. K. Sil'chenko, V. M. Lipunov
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A Torus-Dynamo for Magnetic Fields in Galaxies and Accretion Disks

1990
Accretion disks around compact objects as well as the gaseous components in galaxies often have the form of a torus. To study the structure and behaviour of magnetic fields generated in such rings, a kinematic αω-dynamo is investigated which is working inside a torus embedded into vacuum. Modes symmetric and antisymmetric with respect to the equatorial
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Evidence for initial jet formation by an accretion disk in the radio galaxy M87

New Astronomy Reviews, 2002
Abstract The nearby E0 galaxy M87 in the Virgo Cluster contains one of the nearest examples of a powerful non-thermal jet source. In addition, HST spectroscopy of its nucleus give strong evidence for the presence of a ≈3×109 M⊙ central black hole (corresponding to Schwarzschild radius Rs∼0.0004 pc). These two facts together make M87 the best possible
J.A. Biretta, W. Junor, M. Livio
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Spiral Disk Asymmetries and Other Evidence of Accretion in Nearby Galaxies

1996
Correlations between the stellar disk asymmetries measured in the K-band magnitude, B - V color, residuals from the B-band Tully-Fisher relationship, chemical abundance gradients of nearby spiral galaxies are discussed within the context of a model in which small satellites or H I clouds are accreted onto the outer disks of spiral galaxies.
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Large gaps and high accretion rates in photoevaporative transition disks with a dead zone

Astronomy and Astrophysics, 2021
Matias Garate, Barbara Ercolano, Paola Pinilla   +2 more
exaly  

The growth of supermassive black holes fed by accretion disks

Astronomy and Astrophysics, 2011
J A De Freitas Pacheco
exaly  

Slim Accretion Disks: Theory and Observational Consequences

Universe, 2019
Bozena Czerny, Czerny Bozena
exaly  

From hydrodynamical instability to turbulent viscosity in accretion disks

AIP Conference Proceedings, 2004
Boyarchuk A A, Kuznetsov O A, Bisikalo D V   +2 more
exaly  

Evidence for a correlation between mass accretion rates onto young stars and the mass of their protoplanetary disks

Astronomy and Astrophysics, 2016
Juan Manuel Alcalà, Carlo Felice Manara, Marco Tazzari   +2 more
exaly