GRHydro-MHD: A public general relativistic magneto-hydrodynamics code
THIS IS WORK IN PROGRESS
- Philipp Mösta
- Bruno C. Mundim
- Joshua A. Faber
- Roland Haas
- Scott C. Noble
- Tanja Bode
- Frank Löffler
- Christian D. Ott
- Christian Reisswig
- Erik Schnetter
We present the new general-relativistic magnetohydrodynamics (GRMHD) capabilities of the Einstein Toolkit, an open-source community-driven numerical relativity and
computational relativistic astrophysics code. The GRMHD extension of the Toolkit builds upon previous releases and implements the evolution of relativistic magnetised fluids
in the ideal MHD limit in fully dynamical spacetimes using the same shock-capturing techniques previously applied to hydrodynamical evolution. In order to maintain the
divergence-free character of the magnetic field, the code implements both hyperbolic divergence cleaning and constrained transport schemes. We present test results for a
number of MHD tests in Minkowski and curved spacetimes. Minkowski tests include aligned and oblique planar shocks, cylindrical explosions, magnetic rotors, Alfv\'en waves and
advected loops, as well as a set of tests designed to study the response of the divergence cleaning scheme to numerically generated monopoles. We study the code's performance
in curved spacetimes with spherical accretion onto a black hole on a fixed background spacetime and in fully dynamical spacetimes by evolutions of a magnetised polytropic
neutron star and of the collapse of a magnetised stellar core. Our results agree well with exact solutions where these are available and we demonstrate convergence. All code
and input files used to generate the results are available on http://einsteintoolkit.org. This makes our work fully reproducible and
provides new users with an introduction to applications of the code.
Materials
Monopole Tests
Planar MHD Shocktubes
Cylindrical Shocks
Magnetic Rotor
Alfvén Wave
Loop advection
Bondi Inflow
Magnetized TOV
Rotating Collapse