Thursday 13
Session II-2.2 CMEsand Magnetic clouds in the Helisphere and their impacts on Eart's Environment
Chairman: Sergio Dasso
› 12:15 - 12:30 (15min)
Statistical analysis of magnetic cloud erosion by magnetic reconnection
Alexis Ruffenach  1, *@  , Benoit Lavraud  1@  , Charlie Farrugia  2@  , Pascal Démoulin  3@  , Sergio Dasso  4@  , Jean André Sauvaud  1@  , Primoz Kajdic  1@  , Alexis Rouillard  1@  , Andrii Lynnyk  1@  , Claire Foullon  5@  , Mathew Owens  6@  , Neel Savani  7@  , Janet Luhmann  8@  
1 : Institut de recherche en astrophysique et planétologie  (IRAP)
CNRS : UMR5277, Observatoire Midi-Pyrénées, Université Paul Sabatier - Toulouse III
9 Avenue du Colonel Roche, 31028 Toulouse Cedex 4 -  France
2 : Space Science Center, University of New Hampshire  (UNH)
8 College Road Durham, NH 03824-3525 -  United States
3 : Observatoire de Paris  (LESIA)
Observatoire de Paris, LESIA, INSU, CNRS : UMR8109
5 Place Janssen, Meudon -  France
4 : Institute of Astronomy and Space Physics  (IAFE)
cc 67, suc 28, cp 1428, CABA -  Argentina
5 : Centre for Fusion Space and Astrophysics  -  Website
University of Warwick Gibbet Hill Road Coventry CV4 7AL -  United Kingdom
6 : Space Environment Physics Group, University of Reading  (UOR)  -  Website
The University of Reading, Whiteknights, PO Box 217, READING, Berkshire, RG6 6AH, United Kingdom -  United Kingdom
7 : University Corporation for Atmospheric Research  (UCAR)
3090 Center Green Drive, Boulder, CO 80301 -  United States
8 : Space Sciences Laboratory  (SSL)  -  Website
7 Gauss Way, Berkeley, CA 94720 -  United States
* : Corresponding author

Magnetic clouds (MCs), described as large-scale toroidal magnetic structures, interact with the surrounding interplanetary medium during propagation. It has been suggested in particular that magnetic reconnection may peel off their outer magnetic structure. Recently, Ruffenach et al. (2012) confirmed the occurrence of MC erosion thanks to a multi-spacecraft study combining a set of key signatures expected from this process. The aim of the present study is to extend previous works on the topic to all MCs of solar cycle 23 in order to quantify this phenomenon. This statistical analysis, primarily carried out with WIND and complemented with recent STEREO data, focuses on three signatures. First, based on careful determination of the MCs main axes, we estimate the amount of magnetic flux eroded for each event by analysing the azimuthal flux imbalance during the spacecraft sampling of the flux rope. We also search for magnetic reconnection signatures at the front boundary of the MCs. Finally, we investigate the characteristics of suprathermal electrons in the back region of the MCs. Those electrons are considered to signal potential large-scale topological changes expected from the erosion process.


Online user: 1 RSS Feed