The slow magnetoacoustic mode in the flaring loop

2011/10/06 by Veronika Reznikova, Reznikova, Veronika, Kiyoto Shibasaki +1
Physics and Astronomy · #FOS: Physical sciences #Solar and Stellar Astrophysics (astro-ph.SR) #astro-ph.SR

paper · pdf · doi:10.48550/arxiv.1110.1136

The 11th Asian-Pacific Regional IAU Meeting 2011

arxiv created 2011/10/06 · arxiv updated 2011/10/07

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.

Related

• Reconnection-driven Decaying Pulsations Modulated by Slow Magnetoacoustic Waves
• Relationship between wave processes in sunspots and quasi-periodic pulsations in active region flares
• Localizing Quasiperiodic Pulsations in Hard X-Ray, Microwave, and Lyα Emissions of an X6.4 Flare
• Flare Quasi-Periodic Pulsation Associated with Recurrent Jets
• First Evidence of the Frequency Filtering of Magnetoacoustic Waves in the Flaring Star EK Dra