BATSRUS-Mars

Global Magnetosphere (GM) = BATSRUS BATSRUS, the Block-Adaptive-Tree-Solarwind-Roe-Upwind-Scheme, was developed by the Computational Magnetohydrodynamics (MHD) Group at the University of Michigan, now the Center for Space Environment Modeling (CSEM). It was designed using the Message Passing Interface (MPI) and the Fortran90 standard and executes on a massively parallel computer system. The BATSRUS code solves 3D MHD equations in finite volume form using numerical methods related to Roe's Approximate Riemann Solver. BATSRUS uses an adaptive grid composed of rectangular blocks arranged in varying degrees of spatial refinement levels.

The MHD model has been described in detail by Y. Ma et al. [2014]. The model solves four continuity equations to track the mass densities of the proton and three major ions in the Martian ionosphere: O2+, O+, and CO2+. All ion species share the same velocity and temperature. The Mars-solar wind interaction is self-consistently calculated in the model by including the effects of the crustal anomalies, ion-neutral collisions, and major chemical reactions. The neutral densities of CO2, O, and H are assumed to be spherically symmetric, and the altitude profiles and EUV strength are the same as used for the solar minimum condition in Ma et al. [2004]. The crustal field is calculated based on the 60-order spherical harmonics from Arkani-Hamed [2001].

Simulations are performed int the Mars-centered Solar Ecliptic coordinate system (analogous to GSE for Earth).

General SWMF inputs include setting the number of processors and their allocation to the included models. The date and time to simulate and the length of the run are also necessary.

Inputs to BATSRUS are the solar wind plasma (density, 3D velocity, temperature) and 3D magnetic field values, transformed into GSM coordinates and propagated from the solar wind monitoring satellite's position propagated to the sunward boundary of the simulation domain. The Earth's magnetic field is approximated by a dipole with updated axis orientation and co-rotating inner magnetospheric plasma or with a fixed orientation during the entire simulation run. The orientation angle is updated according to the time simulated or a fixed axis position can be specified independently from the time interval that is simulated.

In addition, an input file with a large number of code options is read in.

Outputs from GM include code restart files and plot files with a wide variety of magnetospheric plasma parameters, such as number densities for H+,O+,O2+,Co2+, pressure P, velocity V_x, V_y, V_z, magnetic field B_x, B_y, B_z, and electric currents, J_x, J_y, J_z.