Forum Springer Astron. Astrophys.
Forum Whats New Search Orders

Astron. Astrophys. 320, 300-304 (1997)

Next Section Table of Contents

Magnetic reconnection mechanism for Type II white-light flares

X.Q. Li 1, 2, M.T. Song 2, F.M. Hu 2 and C. Fang 3

1 CCAST (World Laboratory), P.O.Box 8730, Beijing, P.R. China
2 Purple Mountain Observatory, Academia Sinica, Nanjing 210008, P.R. China
3 Department of Astronomy, Nanjing University, Nanjing 210093, P.R. China

Received 17 July 1996 / Accepted 18 September 1996


Based on the concept that the heating source for Type II white-light flares (WLFs) may be located in the photosphere, we suggest that Type II WLF is reduced by magnetic reconnection in a weakly ionized plasma. A plasmoid may rise by magnetic buoyancy from the subphotosphere into a sunspot region and then expand to form a current sheet in which a type of resistive instability takes place. The effect of neutral atoms on the resistive instability is estimated and found to produce a growth time of typically ten minutes that agrees well with observations.

Key words: magnetohydrodynamics (MHD) – plasmas – Sun: photosphere; flares

Send offprint requests to: X.Q. Li (second address above)


Next Section Table of Contents

© European Southern Observatory (ESO) 1997

Online publication: July 3, 1998