Modelling Fast-Alfvén Mode Conversion Using SPARC

Abstract

We successfully utilise the SPARC code to model fast-Alfvén mode conversion in the region $c_A\gg c_S$ via 3-D MHD numerical simulations of helioseismic waves within constant inclined magnetic field configurations. This was achieved only after empirically modifying the background density and gravitational stratifications in the upper layers of our computational box, as opposed to imposing a traditional Lorentz Force limiter, to ensure a manageable timestep. We found that the latter approach inhibits the fast-Alfvén mode conversion process by severely damping the magnetic flux above the surface.

Proceedings of GONG 2012 / LWS/SDO-5 / SOHO 27 (Eclipse on the Coral Sea: Cycle 24 Ascending) Conference, November 12 -16, 2012, Palm Cove, Australia

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Cited by in corpus (4)

• 3D simulations of realistic power halos in magneto-hydrostatic sunspot atmospheres: linking theory and observation
• Directional Time-Distance Probing of Model Sunspot Atmospheres
• Testing Alfvén wave propagation in a "realistic" set-up of the solar atmosphere
• Sensitivity of helioseismic travel-times to the imposition of a Lorentz force limiter in computational helioseismology