Numerical Simulations of Impulsively Generated MHD Waves in a Solar Coronal Loop

• Autorzy: Selwa M. , Murawski K.
• Języki publikacji: EN

Abstrakty

EN

We study by numerical means the MHD oscillations in a solar coronal loop. Obtained numerical results show that impulses, which are launched in the ambient plasma, excite oscillations in mass density profiles that reveal asymmetry in a cross-section of the loop. This asymmetry is a consequence of the fact that while a part of the loop is compressed its other part is rarefied, resulting from transverse loop oscillations. Due to a lack of spatial resolution this feature has not been observed in the earlier numerical studies of impulsively generated waves. The numerical simulations reveal distinctive time-signatures which are collected at a detection point inside the loop. For the chosen set of physical parameters, these signatures reveal a dozen or so seconds oscillations in the mass density. These oscillations are usually more complex further out from the trigger. A sufficiently large slow magnetosonic wave generates shocks which temporal evolution we trace in mass density profiles.

Słowa kluczowe

EN

Sun: corona; MHD

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2004
• Tom: Vol. 54, No. 2
• Strony: 211--220
• Opis fizyczny: Bibliogr. 18 poz., rys., wykr., zdj.

Twórcy

autor

Selwa M.

• Institute of Physics, UMCS, ul. Radziszewskiego 10, 20-031 Lublin, Poland

autor

Murawski K.

• Institute of Physics, UMCS, ul. Radziszewskiego 10, 20-031 Lublin, Poland

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