Fulguraciones Solares en Regiones Activas Interactuantes

BAGALÁ. L.G.; ROVIRA, M.G.; MANDRINI, C.H.; DÉMOULIN, P.

San Juan

Congreso; 41 Reunión Anual de la Asociación Argentina de Astronomía; 1997

Asociación Argentina de Astronomía

We present a topological approach for the 30th January 1992 solar flares of AR 7031. We study Halpha and soft X-ray emission for the most important flares, and compare these brightenings with the properties of the field-line linkage of the underlying magnetic region. The coronal magnetic field is computed from the observed photospheric field using a linear force-free extrapolation and the regions of drastic change in field-line linkage (called ``quasi-separatrix layers'' or QSLs) are determined by a computer algorithm. We find that a feature common to the two flares studied is the presence of QSLs where Halpha flare kernels are observed. The extrapolated coronal field lines representing these structures have their photospheric footpoints located at both sides of QSLs, as expected if 3D magnetic reconnection were occurring at QSLs. These results allow us to constrain present models of solar flares.