Research Activities > Programs > Matter and Electromagnetic Fields in Strong Gravity

Matter and Electromagnetic Fields in Strong Gravity

CSIC Building (#406), Seminar Room 4122.

Global Simulations of Black Hole Accretion

John Hawley

University of Virginia

Abstract:   Numerical simulations provide a way to investigate the dynamics of accretion flows directly with far fewer limitations compared to analytic models. Because magnetic fields are fundamentally important for jets and disks, and because we now know that magnetic turbulence accounts for the internal stress, the governing equations are those of compressible magnetohydrodynamics (MHD). Accretion disk dynamics can thus be investigated using three-dimensional MHD simulation codes that employ both global and local computational domains. Although it is not yet possible to do fully global time dependent radiation transport in disk models, the observational implications of these simulations can be investigated using simple emission and absorption models coupled with relativistic ray tracing. The time and length-scales involved make such simulations challenging, but even the first results are intriguing. They have revealed details about time-dependent properties of disks, magnetic disk dynamos, jet launching mechanisms, and the dynamical properties of systems other than the standard thin disk. As the capabilities of computational hardware increase, and the development of advanced numerical codes continues, our theoretical understanding of accretion physics will substantially increase.

University of Maryland    

UM Home | Directories | Calendar
Maintained by CSCAMM
Direct questions and comments to

CSCAMM is part of the
College of Computer, Mathematical & Natural Sciences (CMNS)