HR: 08:15h
AN: SM11C-02    [Abstracts]
TI: Characteristics of the Magnetosheath Electron Boundary Layer Under Northward IMF: Implications for High-Latitude Reconnection
AU: * Lavraud, B
EM: lavraud@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Science, MS D466, Los Alamos, NM 87545 United States
AU: Thomsen, M F
EM: mthomsen@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Science, MS D466, Los Alamos, NM 87545 United States
AU: Taylor, M G
EM: mggt@mssl.ucl.ac.uk
AF: Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey, GBR RH5 6NT
AU: Wang, Y L
EM: ywang@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Science, MS D466, Los Alamos, NM 87545 United States
AU: Phan, T D
EM: phan@ssl.berkeley.edu
AF: Space Science Laboratory, Berkeley, Space Science Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720 United States
AU: Schwartz, S J
EM: s.j.schwartz@qmul.ac.uk
AF: Queen Mary, University of London, Astronomy Unit, Queen Mary, University of London, London, E1 4NS United Kingdom
AU: Elphic, R C
EM: relphic@lanl.gov
AF: Los Alamos National Laboratory, Space and Atmospheric Science, MS D466, Los Alamos, NM 87545 United States
AU: Fazakerley, A
EM: anf@mssl.ucl.ac.uk
AF: Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey, GBR RH5 6NT
AU: Reme, H
EM: reme@cesr.fr
AF: Centre d'Etude Spatiale des Rayonnements, 9 ave du colonel roche, Cedex 4, Toulouse, 31028 France
AU: Balogh, A
EM: a.balogh@ic.ac.uk
AF: Blackett Laboratory, Imperial College, South Kensington campus, London, SW7 2AZ United Kingdom
AB: We analyze Cluster data to explore the statistical properties of the magnetosheath electron boundary layer, observed outside the high-latitude dayside magnetopause, under northward IMF. The presence of heated magnetosheath electrons coincident with the normal cool magnetosheath ion population in this layer is taken as the signature of magnetosheath field lines that have reconnected with the high-latitude magnetic field of the earth. We investigate the dependence of the presence and directionality of heated magnetosheath electrons on the dipole tilt angle and the IMF tilt angle. The recurrent presence of bi-directional heated electrons outside the probable magnetopause suggests that magnetosheath field lines may frequently reconnect in both hemispheres. We further investigate the occurrence of such bi-directional heated electrons outside the magnetopause as a function of the IMF clock angle orientation. The findings are discussed in the context of double high-latitude reconnection as a possible mechanism for low-latitude boundary layer, and eventually cold, dense plasma sheet formation under northward IMF.
DE: 2134 Interplanetary magnetic fields
DE: 2164 Solar wind plasma
DE: 2724 Magnetopause, cusp, and boundary layers
DE: 2784 Solar wind/magnetosphere interactions
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting