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arXiv · 1110.1136

The slow magnetoacoustic mode in the flaring loop

Veronika Reznikova·Kiyoto Shibasaki
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Abstract

We studied long duration flare observed with Nobeyama Radioheliograph at frequencies 17 and 34 GHz and with Ramaty High Energy Solar Spectroscopic Imager at 25-50 keV. We found that microwave and hard X-ray emission variation contain well-pronounced periodicity with the oscillation period growing from 2.5 to 5 min. Analysis of the loop length and plasma temperature evolution during the flare allowed to interpret the quasi-periodic pulsations in terms of the second standing harmonics of the slow magnetoacoustic mode. This mode can be generated by the initial impulsive energy release and work as a trigger for the repeated energy releases.

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Veronika Reznikova, Kiyoto Shibasaki. 2011-10-06. The slow magnetoacoustic mode in the flaring loop. https://arxiv.org/abs/1110.1136

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