Multi-wavelength Fourier Observations of Solar Acoustic Waves Near Active Regions with GONG and SDO AIA
Abstract
Active regions on the Sun are abundant with a variety of waves that are both acoustically helioseismic and magnetohydrodynamic in nature. The occurrence of a solar flare can disrupt these waves, through MHD mode-mixing or scattering by the excitation of these waves. We take a multi-wavelength observational approach to understand the source of these waves by studying active regions where flaring activity occurs. Our approach is to search for signals within a time series of images by producing multi-frequency power map movies utilizing a Fast Fourier Transform (FFT) algorithm. We study active regions both spatially and temporally and correlate this method over multiple wavelengths. By surveying the active regions on multiple wavelengths we are able to observe the behavior of these waves at different heights within the Solar atmosphere. In our pilot study with GONG H-alpha we are able to detect enhancements of power around active regions in the lower frequency bands which may arise from an instability in the chromosphere. Further in our study we take multi-wavelength measurements utilizing NASA's SDO AIA 1700, 1600 and 304. In our power map movies of the chromosphere we are able to see a subtle propagating feature moving outward from the center of the flare; this could be an MHD-wave propagating outward by the flaring event or indicative of acoustic power halos. We are in the initial stages of this study understanding the behaviors of these waves which could one day contribute to understanding the mechanism responsible for their formation; that has not yet been explained.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMSH14B..03M
- Keywords:
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- 7599 General or miscellaneous;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMYDE: 7899 General or miscellaneous;
- SPACE PLASMA PHYSICSDE: 7999 General or miscellaneous;
- SPACE WEATHER