Filament activity and photospheric magnetic evolution related to flares
Beijing Astronomical Observatory, National Astronomical Observatories, Chinese Academy of Science, Beijing 100012, PR China
2 Yunnan Astronomical Observatory, Chinese Academy of Science, Kunming 650011, PR China e-mail: firstname.lastname@example.org
Corresponding author: Y. Jiang, email@example.com
Accepted: 25 August 2000
Three successive activations of an active-region filament were observed over a period of eight hours. Each disturbance showed distinctive characteristics and was followed by a flare of different properties. The filament had one end rooted in strong -sunspots. During the first activation, the filament rose up at the rooting end and detached from the -sunspots while its main body remained in place and separated into two twisted threads. During the second activation, only one thread was disturbed and finally disappeared; twisted threads, however, appeared during the third activation. The evolution of photospheric magnetic fields, associated with the filament disturbances, was characterized by squeezing and shearing of -sunspots, flux cancellation and emergence beneath the two ends of the filaments. Our data suggests that magnetic reconnection in the photospheric layer is the likely cause of filament destabilisation.
Key words: Sun: prominences / Sun: filaments / Sun: activity / Sun: flares / Sun: magnetic fields
© ESO, 2001