Magnetic Flux Erosion and Redistribution during CME Propagation

Tuesday, 16 December 2014: 10:20 AM
Benoit Lavraud1, Alexis Ruffenach2, Ward Manchester3, Charles J Farrugia4, Pascal Demoulin5, Sergio Dasso6, Jean-Andre Sauvaud1, Alexis P Rouillard1, Claire Foullon7, Mathew James Owens8, Neel Savani9, Primoz Kajdic10, Janet G Luhmann11 and Antoinette Broe Galvin12, (1)IRAP/CNRS, Toulouse, France, (2)IRAP, Toulouse, France, (3)University of Michigan, Ann Arbor, MI, United States, (4)University of New Hampshire Main Campus, Durham, NH, United States, (5)Paris Observatory Meudon, Meudon, France, (6)University of Buenos Aires, Buenos Aires, Argentina, (7)University of Exeter, Exeter, United Kingdom, (8)University of Reading, Reading, United Kingdom, (9)Naval Research Laboratory, Washington, DC, United States, (10)European Space Research and Technology Centre, Noordwijk, Netherlands, (11)University of California Berkeley, Berkeley, CA, United States, (12)Univ of New Hampshire, Durham, NH, United States
We will review recent works which highlight the occurrence of magnetic flux erosion and redistribution at the front of coronal mass ejections (when they have the structure of a well-defined magnetic cloud). Two main processes have been found and will be presented. The first comes from the occurrence of magnetic reconnection between the magnetic cloud and its sheath ahead, leading to magnetic flux erosion and redistribution, with associated large scale topological changes. The second may occur when dense filament material in the coronal mass ejection pushes its way through the structure and comes in direct contact with the shocked plasma in the sheath ahead. This leads to diverging non-radial flows in front of the CME which transport poloidal flux of the flux rope to the sides of the magnetic cloud.