Coupling between radial and torsional oscillations in a magnetized plasma and possible stellar applications
نویسنده
چکیده
The weakly non-linear interaction of slow magnetoacoustic and torsional Alfvén waves propagating along an unperturbed poloidal magnetic field in a stellar interior is studied in the high plasma β limit. It is shown that slow magnetoacoustic waves parametrically drive torsional modes with the half frequency and wave number. Therefore global slow magnetoacoustic waves which have a radial velocity polarization, may amplify the torsional oscillations. Possible applications of this mechanism to the Sun and binary stars are briefly discussed. Subject headings: Stars:magnetic fields – Stars:oscillations – Magnetohydrodynamics (MHD) – Waves
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