INVESTIGADORES
MANDRINI Cristina Hemilse
congresos y reuniones científicas
Título:
Statistical analysis of magnetic twist properties of ARs from magnetic tongues
Autor/es:
POISSON, M.; LÓPEZ FUENTES, M.C.; MANDRINI, C.H.; DÉMOULIN, P.
Lugar:
Cuzco
Reunión:
Congreso; X Conferencia Latinoamericana de Geofísica Espacial; 2014
Institución organizadora:
Asociación Latinoamericana de Geofísica Espacial - International Space Weather Initiative
Resumen:
We analyze the distribution of the magnetic helicity
properties of almost 200 active regions (ARs) during one and a half solar
cycles (full Cycle 23 and half Cycle 24). We base our study in the magnetic
twist inferred from the observed effects of magnetic tongues in SOHO/MDI
photospheric magnetograms of bipolar ARs. Magnetic tongues are produced by the
photospheric projection of the azimuthal component of the magnetic field around
the axis of the emerging twisted flux-tubes that form ARs. We use a recently
developed technique to characterize the tongues that is based in the computation
of the polarity inversion line of the regions (see also the oral presentation
"Active regions twist from magnetic tongues and force-free coronal
models" by López Fuentes et al., in this meeting). We analyze if the the
degree of twist of ARs is cycle dependent and if it is related to other AR
properties, such as the maximum magnetic flux and their latitude. We also
compare our results with other known helicity properties of ARs from the
literature. We discuss our results in the frame of the mechanisms of magnetic
field and helicity generation in the Sun and the observed distribution of
activity events such as flares and coronal mass ejections along the cycle.