IAFE   05512
INSTITUTO DE ASTRONOMIA Y FISICA DEL ESPACIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Magnetic clouds: An statistical study of their global magnetohydrodynamic magnitudes
Autor/es:
GULISANO A.M.; DASSO S.; MANDRINI C.H.; DEMOULIN P.
Lugar:
Beijing, China
Reunión:
Conferencia; 36th COSPAR Scientific Assembly. Held 16 - 23 July 2006, in Beijing, China.; 2006
Institución organizadora:
COSPAR
Resumen:
Magnetic clouds MCs are highly magnetized plasma structures that have a low proton temperature and a magnetic field vector that rotates when seen by a heliospheric observer More than 20 years of observations of magnetic and plasma properties of MCs at 1 AU have provided significant knowledge on their magnetic structure However because in situ observations only give information along the one-dimensional trajectory of the spacecraft its real 3D magnetic configuration remains still unknown We study a set of 20 magnetic clouds observed by the Wind spacecraft at 1 AU during a solar minimum We explore different models force free and non-force free fields and two different methods one is a simultaneous fitting that let us take the minimum distance from the cloud axis to the spacecraft the impact parameter p different from zero to reconstruct the magnetic structure of clouds from in situ observations Thus for each cloud and for each model method we determine the cloud axis orientation p and the two physical free parameters of each model the twist and the magnetic field intensity both at the cloud axis Then for every cloud we analyze the variation of the computed amounts of magnetic flux and helicity using the different approaches We generate a set of synthetic clouds by changing the space of parameter that represents the possible orientations and p values for real clouds and then we model them using our code to check the validity of our numerical tools