The Flux of Flux Ropes Embedded Within Magnetic Clouds Near 5 AU

Abstract

Magnetic clouds (MCs) are an important kind of interplanetary coronal mass ejections and generally treated as giant flux ropes. Previous researches indicates that the rope structure of MCs may be destructed as they move away from the solar surface. In this paper, we made a statistic study of the azimuthal flux of flux ropes embedded within MCs near 5 AU. The average azimuthal flux of the rope was estimated to be 2.42×1012Wb/Au, less than 20% of that near 1 AU. The rope structure occupied from 30% to 100% of the magnetic cloud interval with an average of 69%. The results presented here indicate that the rope structure of MCs still can be efficiently destructed as they move out beyond 1 AU and treating them as flux ropes, at least beyond 1 AU, may not be appropriate.