Twisting Flux Tubes as a cause of Micro-Flaring Activity

TL;DR

This study investigates how twisting flux tubes may trigger micro-flaring activity in the solar atmosphere, using high-cadence optical observations and wavelet analysis to identify oscillatory signatures and flux tube twisting.

Contribution

It introduces new observational evidence linking flux tube twisting to micro-flare initiation, supported by high-resolution imaging and wavelet analysis.

Findings

Oscillations with periods of 15 to 370 seconds detected.

Twisting of oscillation sites correlates with micro-flare events.

Average twist velocity of 8.1 km/s measured.

Abstract

High-cadence optical observations of an H-alpha blue-wing bright point near solar AR NOAA 10794 are presented. The data were obtained with the Dunn Solar Telescope at the National Solar Observatory/Sacramento Peak using a newly developed camera system, the Rapid Dual Imager. Wavelet analysis is undertaken to search for intensity-related oscillatory signatures, and periodicities ranging from 15 to 370 s are found with significance levels exceeding 95%. During two separate microflaring events, oscillation sites surrounding the bright point are observed to twist. We relate the twisting of the oscillation sites to the twisting of physical flux tubes, thus giving rise to reconnection phenomena. We derive an average twist velocity of 8.1 km/s and detect a peak in the emitted flux between twist angles of 180 and 230 degrees.