From the photosphere to the interplanetary medium: Verification of the magnetic helicity sign

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

Malargue, Mendoza, Argentina

Congreso; 50 Reunión de la Asociación Argentina de Astronomía; 2007

The helicity sign of the solar magnetic field exhibits a hemispheric preference. On a certain statistical base, it is negative (positive) in the northern (southern) hemisphere. In this work we study a set of active regions, observed from 1997 to 2001, for which we can determine the magnetic helicity sign from the evolution of their polarities during flux emergence. We confirm this sign analyzing the coronal field of the studied regions. Then, we combine this analysis with ``in situ'' observations of the magnetic clouds associated with the coronal mass ejections that occurred in those regions. Finally, we find that the helicity sign predicted by the distribution of the photospheric flux agrees with the one observed at coronal and interplanetary level.