HR: 0800h
AN: SM21B-0370    [Abstracts]
TI: Cluster Measurements of Fast Magnetic Reconnection in Earth's Magnetotail
AU: * xiao, C
EM: cjxiao@ourstar.bao.ac.cn
AF: National Astronomical Observatories, Chinese Academy of Science, No. A20, Datun Street, Beijing, 100012 China
AU: Pu, Z
EM: zypu@pku.edu.cn
AF: School of Earth and Space Science, Peking University, No. 5, Yiheyuan Street, Beijing, 100871 China
AU: Ma, Z
EM: zhiwei-ma@uiowa.edu
AF: Institute of Plasma physics, Chinese Academy of Science, Hefei, 230031 China
AU: Wang, X
EM: xgwang@dltu.edu.cn
AF: CAST, Dalian University of Technology, Dalian, 116024 China
AU: Fu, S
EM: suiyanfu@pku.edu.cn
AF: School of Earth and Space Science, Peking University, No. 5, Yiheyuan Street, Beijing, 100871 China
AU: Phan, T
EM: phan@ssl.berkeley.edu
AF: Space Sciences Laboratory, University of California, Berkeley, California, 01-510-643 United States
AU: Zong, Q
EM: zong@bu.edu
AF: Center for Space Physics, Boston University, Boston, 02215 United States
AU: Liu, Z
EM: liu@center.cssar.ac.cn
AF: CSSAR, Chinese Academy of Science, Beijing, 100080 China
AU: Glassmeier, K
EM: kh.glassmeier@tu-braunschweig.de
AF: Institut of Geophysik und Extraterrestrische Physik, Technische Universit„t Braunschweig, Braunschweig, D-38106 Germany
AU: Balogh, A
EM: a.balogh@imperial.ac.uk
AF: Blackett Laboratory, Imperial College, London, SW7 2BZ United Kingdom
AU: Reme, H
EM: henri.reme@cesr.fr
AF: Centre d'Etude Spatiale des Rayonnements, BP 4346, Toulouse, 31028 France
AU: Dandouras, I
EM: iannis.dandour@cesr.fr
AF: Centre d'Etude Spatiale des Rayonnements, BP 4346, Toulouse, 31028 France
AU: Korth, A
EM: kort@mps.mpg.de
AF: MPI for Solar Syatem Reasearch, Katlenburg-Lindau, Lindau, 37191 Germany
AU: Fraenz, M
EM: fraenz@mps.mpg.de
AF: MPI for Solar Syatem Reasearch, Katlenburg-Lindau, Lindau, 37191 Germany
AU: Fazakerley, A
EM: anf@mssl.ud.ac.uk
AF: Mullard Space science laboratory, University College London, London, RH5 6NT United Kingdom
AU: Escoubet, C
EM: philippe.escoubet@esa.int
AF: ESA/ESTEC, Postbus 299, Noordwijk, 2200 AG Netherlands
AB: Fast magnetic reconnection is crucial to explosive processes in magnetospheres, solar and laboratory plasmas, and other astrophysical objects where magnetic energy is rapidly converted to kinetic and thermal energies. To be responsible for energy conversion in dynamic events such as solar flares and Earth's substorms, the reconnection rate R_rec has to be as high as ~ 0.1, in Alfvénic scale. Though reconnection has been studied in many theoretical models and numerical simulations, ultimate confirmation of the fast process must be achieved by detecting the reconnection rate itself and associated dimensions of the diffusion region with multi-spacecraft measurements. We report here a fortuitous multiple traversing of Cluster constellation of four-spacecraft through a diffusion region in the Earth's magnetotail on 15 September, 2001, as satellites were meandering around the X-line for a short period. Based on observed magnetic field and plasma data, we directly obtain a fast reconnection rate of R_rec=V_in/V{A}~ 0.1. The result is the first reliable evidence of fast reconnection in magnetospheric plasmas and provides a solid observation basis for theories and simulations of collisionless fast reconnection. The characteristic sizes of the diffusion region L_z ~ 0.9 d_i(= 460 km), and L_x ~ L_x~(3.3-5.1)d_i are also measured. The length of the diffusion region is determined for the first time based on observations, and further supports the fast reconnection rate measurement and casts light onto the physics inside the diffusion region. Furthermore, other features detected during the event all match the previous observations and simulations very well. These outcomes establish a comprehensive overview of fast reconnection in the ion inertial scale.
DE: 2723 Magnetic reconnection (7526, 7835)
DE: 2744 Magnetotail
DE: 2790 Substorms
DE: 7526 Magnetic reconnection (2723, 7835)
DE: 7835 Magnetic reconnection (2723, 7526)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005