3D Numerical Simulations of f-Mode Propagation Through Magnetic Flux Tubes

Abstract

Three-dimensional numerical simulations have been used to study the scattering of a surface-gravity wave packet by vertical magnetic flux tubes, with radii from 200 km to 3 Mm, embedded in stratified polytropic atmosphere. The scattered wave was found to consist primarily of m=0 (axisymmetric) and m=1 modes. It was found that the ratio of the amplitude of these two modes is strongly dependant on the radius of the flux tube: The kink mode is the dominant mode excited in tubes with a small radius while the sausage mode is dominant for large tubes. Simulations of this type provide a simple, efficient and robust way to start understanding the seismic signature of flux tubes, which have recently began to be observed.

14 pages, 10 figures, accepted for Solar Physics (Topical issue in Helio- and Asteroseismology 2010)

References in corpus (6)

• The solar magnetic field
• Non-linear numerical simulations of magneto-acoustic wave propagation in small-scale flux tubes
• Seismic Halos Around Active Regions: An MHD Theory
• SLiM: a code for the simulation of wave propagation through an inhomogeneous, magnetised solar atmosphere
• Scattering of acoustic waves by a magnetic cylinder
• {\it f}-mode interactions with thin flux tubes: the scattering matrix

Cited by in corpus (2)

• Properties of $p$- and $f$-modes in hydromagnetic turbulence
• Effects of Dynamo-Generated Large-Scale Magnetic Fields on the Surface Gravity ($f$) Mode