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Related papers: Dissipationless Disk Accretion

200 papers

We derive a viscosity from gravitational instability in self-gravitating accretion disks, which has the required properties to account for the observed fast formation of the first super-massive black holes in highly redshifted quasars and…

Astrophysics · Physics 2009-11-11 Wolfgang J. Duschl , Markward Britsch

Particle condensates in general magnetic mirror geometries in high temperature plasma may be caused by a discrete resonance with thermal ion-acoustic background noise near mirror points. The resonance breaks the bounce symmetry, temporally…

Plasma Physics · Physics 2021-07-05 R. A. Treumann , Wolfgang Baumjohann

We review mechanisms for the transport of angular momentum in accretion disks that are low mass, in the sense that the gravitational forces produced by the material in these disks has a negligible effect on disk dynamics. There is no…

Astrophysics · Physics 2007-05-23 ET Vishniac , PH Diamond

We consider viscous rotating accretion flows in which most of the viscously dissipated energy is stored as entropy rather than being radiated. Such advection-dominated flows may occur when the optical depth is either very small or very…

Astrophysics · Physics 2009-10-22 Ramesh Narayan , Insu Yi

Local (shearing box) simulations of the nonlinear evolution of the magnetorotational instability in a collisionless plasma show that angular momentum transport by pressure anisotropy ($p_\perp \ne p_\parallel$, where the directions are…

Astrophysics · Physics 2011-02-11 Prateek Sharma , Eliot Quataert , Gregory W. Hammett , James M. Stone

The effect of an accretion disk on the Blandford-Znajek process and the evolution of a black hole are discussed using a simplified system for the black hole - accretion disk in which the accretion rate is supposed to be dominated by the…

Astrophysics · Physics 2007-05-23 Hyun Kyu Lee , Hui-Kyung Kim

We present the first collisionless realization of two-dimensional axisymmetric black hole accretion consistent with a persistent magnetically arrested disk state. The accretion flow, consisting of an ion-electron disk plasma combined with…

High Energy Astrophysical Phenomena · Physics 2025-05-20 Jesse Vos , Benoit Cerutti , Monika Moscibrodzka , Kyle Parfrey

We present a non-linear numerical model for a geometrically thin accretion disk with the addition of stochastic non-linear fluctuations in the viscous parameter. These numerical realizations attempt to study the stochastic effects on the…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Philip S. Cowperthwaite , Christopher S. Reynolds

The physical mechanism responsible for driving accretion flows in astrophysical accretion disks is commonly thought to be related to the development of plasma instabilities and turbulence. A key question is therefore the determination of…

High Energy Astrophysical Phenomena · Physics 2015-06-03 C. Cremaschini , J. C. Miller , M. Tessarotto

This work describes a laboratory plasma experiment and initial results which should give insight into the magnetic dynamics of accretion discs and jets. A high-speed multiple-frame CCD camera reveals images of the formation and helical…

Astrophysics · Physics 2009-11-07 S. C. Hsu , P. M. Bellan

The self-sustained turbulence which develops in magnetized accretion disks is suppressed in the weakly-ionized, quiescent disks of close binary stars. Because accretion still proceeds during quiescence, another viscosity mechanism operates…

Astrophysics · Physics 2009-10-31 Kristen Menou

Models of the formation, evolution and photoevaporation of circumstellar disks are an essential ingredient in many theories of the formation of planetary systems. The ratio of disk mass over stellar mass in the circumstellar phase of a disk…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. Visser , C. P. Dullemond

We analyze a two dimensional viscoresistive magnetohydrodynamical (MHD) model for a thin accretion disk which reconciles the crystalline structure outlined in [Coppi(2005), Coppi and Rousseau(2006)] with real microscopic and macroscopic…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Riccardo Benini , Giovanni Montani , Jacopo Petitta

We numerically investigate the hydrodynamics of accretion disk reversal and relate our findings to the observed spin-rate changes in the accreting X-ray pulsar GX~1+4. In this system, which accretes from a slow wind, the accretion disk…

Astrophysics · Physics 2009-10-31 James R. Murray , Martijn de Kool , Jianke Li

In a companion paper, we reported the self-consistent formation of quasar accretion disks with inflow rates $\sim 10\,{\rm M_{\odot}\,yr^{-1}}$ down to <300 Schwarzschild radii from cosmological…

We calculate the amount of angular momentum that thermal photons carry out of a viscous black hole accretion disc, due to the strong Doppler shift imparted to them by the high orbital velocity of the radiating disc material. While the…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Jarrett L. Johnson

Planets form inside protostellar disks in a dead zone where the electrical resistivity of the gas is too high for magnetic forces to drive turbulence. We show that much of the dead zone nevertheless is active and flows toward the star while…

Astrophysics · Physics 2009-11-13 N. J. Turner , T. Sano

We present results from the first 3D kinetic numerical simulation of magnetorotational turbulence and dynamo, using the local shearing-box model of a collisionless accretion disc. The kinetic magnetorotational instability grows from a…

High Energy Astrophysical Phenomena · Physics 2016-12-07 Matthew W. Kunz , James M. Stone , Eliot Quataert

Magnetic flux redistribution lies at the heart of the problem of star formation in dense cores of molecular clouds that are magnetized to a realistic level. If all of the magnetic flux of a typical core were to be dragged into the central…

Solar and Stellar Astrophysics · Physics 2015-06-05 Ruben Krasnopolsky , Zhi-Yun Li , Hsien Shang , Bo Zhao

We show that the removal of angular momentum is possible in the presence of large scale magnetic stresses in geometrically thick, advective, sub-Keplerian accretion flows around black holes in steady-state, in the complete absence of…

High Energy Astrophysical Phenomena · Physics 2015-07-03 Banibrata Mukhopadhyay , Koushik Chatterjee