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Related papers: Accretion-Ablation Mechanics

200 papers

Spherically symmetric accretion incorporating self-gravity constitutes a three-point boundary value problem (TPBVP) governed by constraints at the outer boundary, sonic point, and accretor surface. Previous studies have two limitations:…

High Energy Astrophysical Phenomena · Physics 2025-07-04 Cheng-Liang Jiao , Er-gang Zhao , Liying Zhu , Xiang-dong Shi

Both numerical simulations and observations indicate that in an advection-dominated accretion flow most of the accretion material supplied at the outer boundary will not reach the inner boundary. Rather, they are lost via outflow.…

Astrophysics · Physics 2012-07-16 Fu-Guo Xie , Feng Yuan

In dissipative ordinary differential equation systems different time scales cause anisotropic phase volume contraction along solution trajectories. Model reduction methods exploit this for simplifying chemical kinetics via a time scale…

Dynamical Systems · Mathematics 2011-01-13 Dirk Lebiedz , Volkmar Reinhardt , Jochen Siehr

Three-dimensional central symmetric bodies different from spheres that can float in all orientations are considered. For relative density rho=1/2 there are solutions, if holes in the body are allowed. For rho different from 1/2 the body is…

Classical Physics · Physics 2009-04-22 Franz Wegner

In this third study of the 'Resolving supermAssive Black hole Binaries In galacTic hydrodynamical Simulations' (RABBITS) series we develop and implement a geometrically thin relativistic accretion disc model, which self-consistently evolves…

Understanding how accretion proceeds in proto-planetary discs and more generally their dynamics is a crucial issue for explaining the conditions in which planets form. The role that accretion of gas from the surrounding molecular cloud onto…

Astrophysics of Galaxies · Physics 2017-03-15 Patrick Hennebelle , Geoffroy Lesur , Sébastien Fromang

We investigate several problems in relativity and particle physics where symmetries play a central role; in all cases geometric properties of Lie groups and their quotients are related to physical effects. The first part is concerned with…

General Relativity and Quantum Cosmology · Physics 2011-03-04 Steffen Gielen

A new computational scheme is developed to study gas accretion from a circumbinary disk. The scheme decomposes the gas velocity into two components one of which denotes the Keplerian rotation and the other of which does the deviation from…

Solar and Stellar Astrophysics · Physics 2014-11-20 Tomoyuki Hanawa , Yasuhiro Ochi , Koichi Ando

In this paper, we develop the analysis of a two-dimensional magnetohydrodynamical configuration for an axially symmetric and rotating plasma (embedded in a dipole like magnetic field), modeling the structure of a thin accretion disk around…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Giovanni Montani , Riccardo Benini

We study the coupled small-amplitude motion of the mechanical system consisting of infinitely deep water and a structure immersed in it. The former is bounded above by a free surface, whereas the latter is formed by an arbitrary finite…

Mathematical Physics · Physics 2014-10-23 Nikolay Kuznetsov , Oleg Motygin

Non-radiating, advection-dominated, accretion flows are convectively unstable. We calculate the two-dimensional (r-theta) structure of such flows assuming that (1) convection transports angular momentum inwards, opposite to normal viscosity…

Astrophysics · Physics 2009-10-31 Eliot Quataert , Andrei Gruzinov

The conventional formulation of the non-adiabatic (Aharonov-Anandan) phase is based on the equivalence class $\{e^{i\alpha(t)}\psi(t,\vec{x})\}$ which is not a symmetry of the Schr\"{o}dinger equation. This equivalence class when understood…

Quantum Physics · Physics 2009-11-13 Kazuo Fujikawa

We have considered precession in accretion disks in which a second moment of inertia relative to an axis perpendicular to the axis of rotation may be very important. This formalism, that takes into account the precession contribution to the…

Astrophysics · Physics 2007-10-17 Cesar Meirelles Filho

This paper continues the analysis of a set of general relativistic 3D MHD simulations of accreting tori in the Kerr metric with different black hole spins. We focus on bound matter inside the initial pressure maximum, where the…

Astrophysics · Physics 2009-11-10 Julian H. Krolik , John F. Hawley , Shigenobu Hirose

We study the adiabatic accretion process of ordinary baryonic gas onto spherically symmetric black holes in Einstein-Maxwell-scalar theory, with two parameters $\alpha$ and $\beta$ in the coupling term. Especially, we demonstrate the range…

General Relativity and Quantum Cosmology · Physics 2022-04-27 Haiyuan Feng , Miao Li , Gui-Rong Liang , Rong-Jia Yang

We are concerned with underlying connections between fluids, elasticity, isometric embedding of Riemannian manifolds, and the existence of wrinkled solutions of the associated nonlinear partial differential equations. In this paper, we…

Analysis of PDEs · Mathematics 2017-08-29 Amit Acharya , Gui-Qiang Chen , Siran Li , Marshall Slemrod , Dehua Wang

In the present work, it is shown that the problem of the accelerating expansion of the Universe can be directly solved by applying Einstein geometrization philosophy in a wider geometry. The geometric structure used to fulfil the aim of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. I. Wanas

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

Observations are providing increasingly detailed quantitative information about the accretion flows that power such high energy systems as X-ray binaries and active galactic nuclei. Analytic models of such systems must rely on assumptions…

Astrophysics · Physics 2008-11-26 J. F. Hawley , J. -P. De Villiers

In this paper, we present the stationary axisymmetric configuration of a resistive magnetised thick accretion disc in the vicinity of external gravity and intrinsic dipolar magnetic field of a slowly rotating black hole. The plasma is…

High Energy Astrophysical Phenomena · Physics 2020-03-18 Mahboobeh Shaghaghian