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arXiv · 1706.05427

Slow-Mode Oscillations of Hot Loops Excited at Flaring Footpoints

Tongjiang Wang·Wei Liu·Leon Ofman·Joseph M. Davila
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Abstract

The analysis of a hot loop oscillation event using SOHO/SUMER, GOES/SXI, and RHESSI observations is presented. Damped Doppler shift oscillations were detected in the Fe XIX line by SUMER, and interpreted as a fundamental standing slow mode. The evolution of soft X-ray emission from GOES/SXI and hard X-ray sources from RHESSI suggests that the oscillations of a large loop are triggered by a small flare, which may be produced by interaction (local reconnection) of this large loop with a small loop at its footpoint. This study provides clear evidence supporting our early conjecture that the slow-mode standing waves in hot coronal loops are excited by impulsive heating (small or microflares) at the loop's footpoint.

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Tongjiang Wang, Wei Liu, Leon Ofman, Joseph M. Davila. 2017-06-16. Slow-Mode Oscillations of Hot Loops Excited at Flaring Footpoints. https://arxiv.org/abs/1706.05427

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