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arXiv · 1406.1869

Torsional Alfven waves and the period ratio P_1/P_2 in spicules

Hossein Ebadi·Sadagat Shahmorad
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Abstract

The effects of both density stratification and magnetic field expansion on torsional Alfven waves in solar spicules are studied. Also, their eigenfrequencies, eigenfunctions, and the period ratio P_1/P_2 are obtained with a novel mathematical method. We showed that under some circumstances this ratio can approach its observational value even though it departs from its canonical value of $2$. Moreover, Eigenfunction height variations show that the oscillations amplitude are increasing towards higher heights which is in agreement with the observations. This means that with a little increase in height, amplitude of oscillations expands due to the significant decrease in the density.

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Hossein Ebadi, Sadagat Shahmorad. 2014-06-07. Torsional Alfven waves and the period ratio P_1/P_2 in spicules. https://doi.org/10.1007/s10509-014-2003-y

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