Electron-Scale Magnetic Structure Observed Adjacent to an Electron Diffusion Region at the Dayside Magnetopause

被引:9
作者
Hoilijoki, S. [1 ]
Ergun, R. E. [1 ,2 ]
Schwartz, S. J. [1 ]
Eriksson, S. [1 ]
Wilder, F. D. [1 ]
Webster, J. M. [3 ]
Ahmadi, N. [1 ]
Le Contel, O. [4 ]
Burch, J. L. [5 ]
Torbert, R. B. [6 ]
Strangeway, R. J. [7 ]
Giles, B. L. [8 ]
机构
[1] Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA
[2] Univ Colorado, Dept Astrophys & Planetary Sci, Boulder, CO 80309 USA
[3] Rice Univ, Dept Phys & Astron, Houston, TX USA
[4] Univ Paris Sud, Sorbonne Univ, CNRS, Ecole Polytech,LPP,Observ Paris, Paris, France
[5] Southwest Res Inst, San Antonio, TX USA
[6] Univ New Hampshire, Dept Phys, Durham, NH 03824 USA
[7] Univ Calif Los Angeles, Dept Earth Planetary & Space Sci, Los Angeles, CA USA
[8] NASA, Goddard Space Flight Ctr, Greenbelt, MD USA
关键词
reconnection; magnetopause; diffusion region; FLUX-TRANSFER EVENTS; MAGNETOSPHERIC MULTISCALE OBSERVATIONS; MMS OBSERVATIONS; ION DIFFUSION; RECONNECTION; FIELD; WAVES; PARALLEL; ACCELERATION; MAGNETOMETER;
D O I
10.1029/2019JA027192
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
In this paper, we present observations made by the Magnetospheric Multiscale (MMS) mission of a small-scale magnetic structure adjacent to a reconnecting current sheet at the dayside magnetopause. While MMS crosses the current sheet, it observes signatures of an electron diffusion region (EDR), including crescent shaped electron velocity distribution functions. Right after the EDR crossing, all spacecraft encounter an electron-scale magnetic structure that can roughly be divided into two parts: a force-free flux rope-like part and a nonforce-free magnetic enhancement. Within the leading force-free part of the structure, the magnetic field component normal to the current sheet exhibits a bipolar signature, suggesting that the structure is flux rope-like. In the trailing edge of the bipolar signature, three spacecraft observe a magnetic enhancement that has an amplitude almost twice the ambient magnetic field. The magnetic peak adjacent to an EDR can be associated with an electron vortex, where the perpendicular current is carried by ExB drifting electrons. The structure is advected tailward along the magnetopause while in the plasma frame, it propagates upstream suggesting that this reconnection event is highly three-dimensional. Fluctuations in the plasma density and magnetic field and large peaks in the parallel electric field observed on the magnetospheric side of the EDR suggest that the current sheet is corrugated due to an electromagnetic drift instability. This or another instability of a thin reconnecting current sheet (e.g., tearing) is a likely cause of the formation of the observed magnetic structure.
引用
收藏
页码:10153 / 10169
页数:17
相关论文
共 76 条
[71]   Multipoint Measurements of the Electron Jet of Symmetric Magnetic Reconnection with a Moderate Guide Field [J].
Wilder, F. D. ;
Ergun, R. E. ;
Eriksson, S. ;
Phan, T. D. ;
Burch, J. L. ;
Ahmadi, N. ;
Goodrich, K. A. ;
Newman, D. L. ;
Trattner, K. J. ;
Torbert, R. B. ;
Giles, B. L. ;
Strangeway, R. J. ;
Magnes, W. ;
Lindqvist, P. -A. ;
Khotyaintsev, Yu-V. .
PHYSICAL REVIEW LETTERS, 2017, 118 (26)
[72]   Magnetospheric Multiscale Observations of Electron Scale Magnetic Peak [J].
Yao, S. T. ;
Shi, Q. Q. ;
Guo, R. L. ;
Yao, Z. H. ;
Tian, A. M. ;
Degeling, A. W. ;
Sun, W. J. ;
Liu, J. ;
Wang, X. G. ;
Zong, Q. G. ;
Zhang, H. ;
Pu, Z. Y. ;
Wang, L. H. ;
Fu, S. Y. ;
Xiao, C. J. ;
Russell, C. T. ;
Giles, B. L. ;
Feng, Y. Y. ;
Xiao, T. ;
Bai, S. C. ;
Shen, X. C. ;
Zhao, L. L. ;
Liu, H. .
GEOPHYSICAL RESEARCH LETTERS, 2018, 45 (02) :527-537
[73]   Observations of kinetic-size magnetic holes in the magnetosheath [J].
Yao, S. T. ;
Wang, X. G. ;
Shi, Q. Q. ;
Pitkanen, T. ;
Hamrin, M. ;
Yao, Z. H. ;
Li, Z. Y. ;
Ji, X. F. ;
De Spiegeleer, A. ;
Xiao, Y. C. ;
Tian, A. M. ;
Pu, Z. Y. ;
Zong, Q. G. ;
Xiao, C. J. ;
Fu, S. Y. ;
Zhang, H. ;
Russell, C. T. ;
Giles, B. L. ;
Guo, R. L. ;
Sun, W. J. ;
Li, W. Y. ;
Zhou, X. Z. ;
Huang, S. Y. ;
Vaverka, J. ;
Nowada, M. ;
Bai, S. C. ;
Wang, M. M. ;
Liu, J. .
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2017, 122 (02) :1990-2000
[74]   Evidence that crater flux transfer events are initial stages of typical flux transfer events [J].
Zhang, H. ;
Kivelson, M. G. ;
Khurana, K. K. ;
McFadden, J. ;
Walker, R. J. ;
Angelopoulos, V. ;
Weygand, J. M. ;
Phan, T. ;
Larson, D. ;
Glassmeier, K. H. ;
Auster, H. U. .
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2010, 115
[75]   Evidence for Secondary Flux Rope Generated by the Electron Kelvin-Helmholtz Instability in a Magnetic Reconnection Diffusion Region [J].
Zhong, Z. H. ;
Tang, R. X. ;
Zhou, M. ;
Deng, X. H. ;
Pang, Y. ;
Paterson, W. R. ;
Giles, B. L. ;
Burch, J. L. ;
Tobert, R. B. ;
Ergun, R. E. ;
Khotyaintsev, Y. V. ;
Lindquist, P. -A. .
PHYSICAL REVIEW LETTERS, 2018, 120 (07)
[76]   Electric field structure inside the secondary island in the reconnection diffusion region [J].
Zhou, M. ;
Deng, X. H. ;
Huang, S. Y. .
PHYSICS OF PLASMAS, 2012, 19 (04)