4:00 PM - 4:15 PM
[PEM12-27] Increasing Amplitude of the Small-scale Motions of the Filaments as the Precursors of their Eruptions
Keywords:Space Weather Prediction, Solar Eruptive Phenomena, Filament, Filament Eruption, Coronal Mass Ejection
For this purpose, we analyzed the solar full disk images captured by Solar Dynamics Doppler Imager (SDDI) installed on Solar Magnetic Activity Research Telescope(SMART) at Hida Observatory, Kyoto University. SDDI can obtain solar full disk images in 73 wavelengths between Hα center - 9 Å and Hα center + 9 Å per 0.25 Å with the time resolution of about 15 seconds. Therefore this instrument can observe unprecedented detailed line-of-sight velocities of filaments. Focusing on this feature, in our previous work we calculated the line-of-sight velocities of the filament observed on 2016 November 5 by utilizing Beckers’ cloud model from before the eruption (Figure, Step 1) and tracked the standard deviation of the line-of-sight velocities inside the filament (Figure, Step 2). As a result, we found an increase of the standard deviation, that is, an increase in the amplitude of line-of-sight velocity of the small-scale motions in the filament about 1 hour before the onset of the eruption.
In this work, we newly found 6 events that showed the increase in the standard deviation of the line-of-sight velocities inside filaments before eruption. The features were seen 1.7 hours before their eruptions on average (standard deviation: 0.75 hours). We concluded that this result can support utilizing the increase of small-scale motions in a solar filament as the precursor of a filament eruption.
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