Magnetic clouds, as subsets of Interplanetary Coronal Mass Ejections, are modulating the interplanetary space. We present six observed magnetic clouds and simulate them according to the circular and the new elliptic cylindrical models. Both models correspond to magnetic clouds attached to the sun and the simulations estimate the characteristics of the clouds, such probable shapes, orientation of their axis, duration, etc. In general, magnetic clouds can be described by closed (attached) cylindrical models, but with an elliptic rather than circular cylindrical shape.

(This presentation is supported by the Greek-Czech Bilateral Cooperation).

Proceedings of the 30th International Cosmic Ray Conference; Rogelio Caballero, Juan Carlos D'Olivo, Gustavo Medina-Tanco, Lukas Nellen, Federico A. Sánchez, José F. Valdés-Galicia (eds.); Universidad Nacional Autónoma de México, Mexico City, Mexico, 2008; Vol. 1 (SH), pages 191-194