HR: 1340h
AN: SM53B-0418    [Abstracts]
TI: Multiple-spacecraft Detection of the Diffusion Region of Magnetic Reconnection by Cluster Mission
AU: * Xiao, C
EM: cjxiao@pku.edu.cn
AF: National Astronomical Observatories, Chinese Academy of Science, Beijing, 100012 China
AU: Pu, Z
EM: zypu@pku.edu.cn
AF: Depart. of Geophysics, Peking University, Beijing, 100871 China
AU: Huang, Z
AF: Depart. of Geophysics, Peking University, Beijing, 100871 China
AU: Fu, s
AF: Depart. of Geophysics, Peking University, Beijing, 100871 China
AU: Liu, Z
AF: CSSAR, Chinese Academy of Science, Beijing, 100080 China
AU: Ma, Z
AF: Institute of plasma phyiscs, Chinese Academy of Science, Anhui, 230031 China
AU: Balogh, A
AF: SAPG, The Blackett Lab, Imperial College, London, SW7 2BZ United Kingdom
AU: Glassmeier, K
AF: IGM, Institut for Geophysik und Meteorologie, Mendelssohnstr, Branuschweig, D-38106 Germany
AU: Reme, H
AF: CESR/CNRC, B.P. 4346, 9 Avenue du Colonel Roche, Toulouse Cede, F-31029 France
AU: Zong, Q
AF: CSP, Boston University, Boston, 02215 United States
AU: Gustafsson, G
AF: Ruhr Univ Bochum, Inst Theoret Phys 4, D-44780 Bochum, Germany, Theoret Phys 4, Bochum, D-44780 Germany
AB: Magnetic reconnection (MR) is the process by which the magnetic field topology changes, accompanying with release and conversion of magnetic energy into kinetic and thermal energy of plasmas. MR occurs in the small localized diffusion region, its global consequence plays a central role in solar wind-magnetosphere interactions. For more than 30 years MR has been the most challenging frontier of space plasma physics. One of unsolved key questions concerns the physics and spatial scales of the diffusion region. Until recently in situ observations of MR have all been taken outside the diffusion region. Measurements inside the diffusion region would help to test and develop the models and theories of reconnection. Four spacecraft Cluster mission provides a unique opportunity to detect small-scale structures in three dimensions in space, including MR area. In the present paper a comprehensive study on the diffusion region in the magnetotail for a typical MR event (09-15-2001) is carried out with the Cluster multiple satellite data. The following new results from this case study are obtained: 1. The magnetic field topology change across the neutral point is observed by simultaneous measurements of 4 Cluster spacecraft. The related plasma flow reversals and the distinct quadrupolar Hall magnetic field components are clearly identified. 2. The thickness of the tail current sheet in the tail is best fitted as Lz=1.3di (di stands for the ion inertial length) based on Cluster multiple-point high resolution (0.05s) magnetic field measurements; the scale length of the diffusion region in the x-direction is determined to be Lx=3.7-5.0di. 3. The MR separatrix angle ŻE is derived to be 15<ŻE<20. The reconnection rate is estimated to be R=0.09-0.12. 4. Energization of energetic ions and electrons is found during the diffusion region crossing. The lower hybrid waves are detected in the vicinity of the diffusion region.
DE: 7835 Magnetic reconnection
DE: 2744 Magnetotail
DE: 2764 Plasma sheet
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting