HR: 1340h
AN: SH13A-0294 [Abstracts]
TI: Generation of Erupting Flux Ropes
by Reconnection Among Smaller Scale Flux Tubes
AU: * Choe, G
EM: gchoe@pppl.gov
AF: Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, NJ 08543-0451
United States
AU: Cheng, C Z
EM: fcheng@pppl.gov
AF: Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, NJ 08543-0451
United States
AU: Cheng, C Z
EM: fcheng@pppl.gov
AF: National Space Organization, 9 Prosperity 1st Road, Hsinchu, 30077
Taiwan
AU: Lee, J
EM: leej@njit.edu
AF: New Jersey Institute of Technology, 323 Martin Luther King Boulevard, Newark, NJ 07102-1982
United States
AB:
In eruptive flares with CMEs, several loop-shaped brightenings are often observed before the major mass ejection loop is
ejected. The distance between the legs of the CME loop is generally much larger than the separation between H alpha flare
ribbons or that between hard X-ray emission features. It can be thus inferred that the large scale erupting flux rope should
be generated by reconnection among flux tubes that are commonly observed in the active region corona. These average scale
flux tubes are energized by vortical motions, which are believed to be present in or below the solar surface and supply a net
magnetic helicity to the coronal plasma system. In this 3D MHD simulation study, we follow the evolution of an idealized
active region composed of several magnetic flux tubes whose original field connectivities are individually discrete. Vortical
motions in the footpoint level are imposed within individual flux tubes so that the longitudinal magnetogram does not change
at all while magnetic shear near the polarity inversion line rapidly increases as could be seen in a vector magnetogram of
an eruptive active region. Magnetic reconnection between the flux tubes results in new field line connections, in which the
distance between the footpoints is considerably larger than the original one. After a certain amount of magnetic flux is
reconnected, a new helical flux rope of a visibly large scale is created and is expelled out of the active region leaving the
underneath field lines open. An observational example corresponding to this simulation will also be presented.
DE: 7509 Corona
DE: 7513 Coronal mass ejections (2101)
DE: 7519 Flares
DE: 7526 Magnetic reconnection (2723, 7835)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005