Magnetohydrodynamics in full general relativity: Formulation and tests

The University of Tokyo, Tōkyō, Japan
Physical review D: Particles and fields (Impact Factor: 4.86). 07/2005; 72(4). DOI: 10.1103/PhysRevD.72.044014
Source: arXiv

ABSTRACT A new implementation for magnetohydrodynamics (MHD) simulations in full general relativity (involving dynamical spacetimes) is presented. In our implementation, Einstein's evolution equations are evolved by a BSSN formalism, MHD equations by a high-resolution central scheme, and induction equation by a constraint transport method. We perform numerical simulations for standard test problems in relativistic MHD, including special relativistic magnetized shocks, general relativistic magnetized Bondi flow in stationary spacetime, and a longterm evolution for self-gravitating system composed of a neutron star and a magnetized disk in full general relativity. In the final test, we illustrate that our implementation can follow winding-up of the magnetic field lines of magnetized and differentially rotating accretion disks around a compact object until saturation, after which magnetically driven wind and angular momentum transport inside the disk turn on. Comment: 28 pages, to be published in Phys. Rev. D

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