Results 161 to 170 of about 321 (187)

The Effects of Satellite Accretion on Disk Galaxies

1987
Over a Hubble time, the disk of a spiral galaxy and its system of satellites can be severely altered by the action of dynamical friction. Satellites sink rapidly to the center of the disk when their orbits bring them within the optical radius. Those satellites in direct orbits with orbital planes close to that of the disk sink the fastest.
openaire   +1 more source

Accretion Disks and the Link Between an AGN and its Host Galaxy

1989
We examine the possible role of accretion disks in bringing matter from the interstellar medium into the central regions of an active galactic nucleus (AGN). Thin axisymmetric accretion disks are not a viable means of transporting fuel to luminous AGNs on scales larger than a fraction of a parsec, because 1) the inflow time scale is too long; and 2 ...
Mitchell C. Begelman, Juhan Frank, Isaac Shlosman   +2 more
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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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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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DYNAMICS OF SPIRAL GALAXIES IN NONLINEAR REGIME - NONLINEAR SOLITARY WAVES IN ACCRETION DISK

Publications of the Astronomical Observatory of Belgrade
Abstract. Theory of accretion disk is subject of several different theoretical models. Here, we list all important effects that can influence the accretion disk dynamics. For each effect, we propose nonlinear solution that is able to overcome linearly unstable structure.
Miroslava Vukčević, Edi Bon, Nataša Bon   +2 more
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Prebiotic Astrochemistry and the Formation of Molecules of Astrobiological Interest in Interstellar Clouds and Protostellar Disks

Chemical Reviews, 2020
Scott A Sandford, Michel Nuevo, Partha P Bera   +2 more
exaly  

A repeating fast radio burst source localized to a nearby spiral galaxy

Nature, 2020
Benito Marcote, Kenzie Nimmo, Jason Hessels   +2 more
exaly  

A single fast radio burst localized to a massive galaxy at cosmological distance

Science, 2019
Keith Bannister, A T Deller, Chris J Phillips   +2 more
exaly  

Evidence for neutrino emission from the nearby active galaxy NGC 1068

Science, 2022
exaly  

The Galaxy in Context: Structural, Kinematic, and Integrated Properties

Annual Review of Astronomy and Astrophysics, 2016
Joss Bland-Hawthorn, Ortwin Gerhard
exaly