Magnetic reconnection in magnetosphere analyzed by field topology : Application to the magnetotail and subsolar region

Abstract : A huge number of works has been already performed on the magnetic reconnection (MR). Different aspects in terms of global behavior or localized kinetic processes have been analyzed with the help of MHD, hybrid or PIC simulations. Herein, a quite different approach is proposed not in terms of identification or efficiency of processes but in terms of field topology (FT). This approach which is almost ignored in magnetospheric community is more commonly accepted by the solar community. Herein, we applied the field topology analysis to results issued from three dimensional self consistent full PIC simulations of the magnetosphere as the southward interplanetary magnetic field (IMF) is varying. Two particular areas have been analyzed where MR can take place: a) in the terrestrial magnetotail: The FT allows to approach the MR in terms of locations and time where/when it can take place without any "a-priori idea" on the mechanism responsible for it. The aim consists in identifying the 3D locations of pairs of null points, and the neutral line linking these pairs. Present simulations show that before the MR all pairs are clustered in certain allocation around in the equatorial plane, while, after MR, the neutral line is broken and the group of null points is split into two groups moving suddenly (north and southward) away from the equatorial plane. b) at the terrestrial subsolar region: The location of this region has been used to evidence a hysteresis behavior of the magnetosphere. This dynamics illustrates the fact the magnetosphere does not retrieve immediately its original configuration (as IMF increases and decreases) and is interpreted as some energy of the solar wind has been absorbed by some irreversible way by the inner magnetosphere during its compression phase. These results show that three-dimensional and temporal effects play a crucial role in the MR identification and hence in the underlying mechanisms responsible for.
Complete list of metadatas

https://hal.archives-ouvertes.fr/hal-00777153
Contributor : Catherine Cardon <>
Submitted on : Wednesday, January 16, 2013 - 11:43:38 PM
Last modification on : Tuesday, May 14, 2019 - 11:10:02 AM

Identifiers

  • HAL Id : hal-00777153, version 1

Citation

D. S. Cai, K. I. Nishikawa, Bertrand Lembège. Magnetic reconnection in magnetosphere analyzed by field topology : Application to the magnetotail and subsolar region. Earth-sun system exploration : variability in Space plasma phenomena, Jan 2011, Kona, Hawaï, United States. ⟨hal-00777153⟩

Share

Metrics

Record views

165