Magnetic flux conservation in magnetic clouds

Magnetic clouds are magnetic structures into interplanetary coronal mass ejections. The structure of magnetic cloud evolves during its travel over the solar wind toward the outermost limit of the heliosphere. Direct observations on magnetic clouds from Helios mission, show us that the magnetic field is reduced and their size grows up with the distance to Sun. The magnetic flux is expected to be conserved if erode processes are not present along the magnetic cloud path into solar wind. This work study this magnetic flux conservation using a set of magnetic cloud observed during the Helios mission.