Vol 22, No 10

Investigation of the Oscillations in a Flare-productive Active Region

Fanpeng Shi, Zongjun Ning and Dong Li


We investigate the oscillations in active region (AR) NOAA 12891, which produces a C2.0 three-ribbon flare accompanying a jet on 2021 November 2. Using the data from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory, the 5 minutes decayless kink oscillations of coronal loops were detected and they are independent of the solar flare. Based on the observed oscillations and seismological diagnostics, we estimate that the Alfvén speed and magnetic field in these coronal loops are around 466 km s−1 and 7.6 G, respectively. Additionally, the flare-related jet shows its plasmoids with 1 minute periodicity same as the intensity fluctuation of nearby flare ribbon. The correlation between the intensity fluctuation of jet and that of flare ribbon indicates that their 1 minute oscillations should originate from the same reconnection process.


Sun: activity – Sun: oscillations – Sun: UV radiation

Full Text