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Accretion Discs in Astrophysics
If we put a particle in a circular orbit around a central gravitating body, it will stay in that orbit. If we then extract energy and angular momentum from the particle we may allow it to spiral
Theory of black hole accretion disks
Part I. Observations of Black Holes: 1. Black holes in our Galaxy: observations P. Charles 2. Black holes in Active Galactic Nuclei: observations G. M. Madejski Part II. Physics Close to a Black
A Hubble Space Telescope Survey of Extended [O III] λ5007 Å Emission in a Far-Infrared-Selected Sample of Seyfert Galaxies: Results
We present the results of a Hubble Space Telescope (HST) survey of extended [O III] emission in a sample of 60 nearby Seyfert galaxies (22 Seyfert 1's and 38 Seyfert 2's), selected by mostly
Competitive accretion in embedded stellar clusters
We investigate the physics of gas accretion in young stellar clusters. Accretion in clusters is a dynamic phenomenon as both the stars and the gas respond to the same gravitational potential.
Photoevaporation of protoplanetary discs - II. Evolutionary models and observable properties
We present a new model for protoplanetary disc evolution. This model combines viscous evolution with photoevaporation of the disc. However, in a companion paper we have shown that at late times such
A simple approach to the evolution of twisted accretion discs
A simple set of equations is introduced which governs the time evolution of a twisted accretion disc. The time evolution is governed by two «viscosities», one governing shear within the plane of the
Hydrodynamical non-radiative accretion flows in two dimensions
Two-dimensional (axially symmetric) numerical hydrodynamical calculations of accretion flows that cannot cool through emission of radiation are presented. The calculations begin from an equilibrium
Magnetohydrodynamical non‐radiative accretion flows in two dimensions
ABSTRA C T We present the results of axisymmetric, time-dependent magnetohydrodynamic simulations of accretion flows around black holes. The calculations begin from a rotationally supported thick
The evolution of black hole mass and spin in active galactic nuclei
It is concluded that supermassive black holes (SMBH) should on average spin moderately, with the mean value a decreasing slowly as the mass increases; SMBH coalescences leave little long-term effect on a; rare examples of massive holes with larger spin parameters could result from prograde coalescence withSMBHs of similar mass, and are most likely to be found in giant ellipticals.