Energy release topology in a multiple-loop solar flare

Journal Article · Fri Nov 15 04:00:00 EST 1985 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/163672· OSTI ID:6282065

Cheng, C; Pallavicini, R; Acton, L W; Tandberg-Hanssen, E

We have studied the temporal and spatial structures of the UV and X-ray emissions and the magnetic field configuration in the 1980 November 12 flare observed from S M M . The UV observations were done in the O V and Fe XXI lines with a spatial resolution of 10''. The observations show that the impulsive UV bursts, and also the hard X-ray bursts by their temporal correlation with the impulsive O V emission, occurred in small localized kernels. By comparing the O V, Fe XXI, and X-ray raster images of the flare with the magnetogram, we identified these emission kernels as footpoints of interacting magnetic flux loops. The temporal evolution of the O V/Fe XXI emission shows that there was considerable preheating in the flare plasma some 8--9 minutes prior to the onset of the main hard X-ray bursts. We interpret the results as indicating that the primary flare energy release occurred in a highly sheared multiloop structure, which lies along a magnetic neutral line. By either beam particle propagation or convective motion, flare energy is transported via a common footpoint to another loop which brightened later. The preheating of the flare plasma is shown to create a more favorable environment for energetic particle acceleration which resulted in the main impulsive hard X-ray bursts.

• Research Organization: E. O. Hulburt Center for Space Research, Naval Research Laboratory
• OSTI ID: 6282065
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 298:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTROMAGNETIC RADIATION
EMISSION
HEATING
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELDS
MAPS
PLASMA
RADIATIONS
SOLAR ACTIVITY
SOLAR FLARES
SOLAR X-RAY BURSTS
SPECTRA
ULTRAVIOLET RADIATION
ULTRAVIOLET SPECTRA
X-RAY SPECTRA