While studying energy release during solar flares, I am also interested in energy accumulation process of flares. Since explosive events often occur around filaments, the study of filament activities could tell us how energy for explosion is accumulated and stored. This is why I investigated gas motions around a filament. (The side reason is that I have a nice chance to use a lot of data of filaments by getting a job at Hida observatory!) We think that the pattern of gas motions is a key to understand energy accumulation process, so we applied Local Correlation Technique (LCT) to G-band image data (Figure 4) and derived photospheric velocity field. We found converging motions arouond a filament. These motions probably have a close relationship to energy build-up of a magnetic arcade overlying the filament (Magara & Kitai 1999).
Magara, T., & Kitai, R. 1999, ApJ, 524, 469