Photospheric evolution of peculiar active regions

LUONI, M.L.; DÉMOULIN, P.; MANDRINI, C.H.; VAN DRIEL-GESZTELYI, L.

Puntareans

Congreso; IX Conferencia Latinoamericana de Geofísica Espacial; 2011

Magnetic flux emergence is responsible for the formation of sunspots and active regions. Bipolar active regions are formed by twisted tubes flux. This twist is characterised by the elongations of the magnetic polarities during flux emergence; these elongations are called "magnetic tongues". In this presentation we analyse the evolution of magnetic tongues during the emergence of two active regions. This shape can be understood as the signature of the azimuthal (poloidal) field component in an emerging flux rope. The spatial organization of the magnetic tongues and the orientation of the polarity inversion line are used as proxies of the magnetic helicity sign of the magnetic field, as well as sigmoids and/or sheared coronal loops.