Finite gyroradius effects in the electron outflow of asymmetric magnetic reconnection

被引：43

作者：

Norgren, C. ^{[1
,2
]}

Graham, D. B. ^{[1
]}

Khotyaintsev, Yu. V. ^{[1
]}

Andre, M. ^{[1
]}

Vaivads, A. ^{[1
]}

Chen, L. -J. ^{[3
,4
]}

Lindqvist, P. -A. ^{[5
]}

Marklund, G. T. ^{[5
]}

Ergun, R. E. ^{[6
]}

Magnes, W. ^{[7
]}

Strangeway, R. J. ^{[8
]}

Russell, C. T. ^{[8
]}

Torbert, R. B. ^{[9
]}

Paterson, W. R. ^{[3
]}

Gershman, D. J. ^{[3
,4
]}

Dorelli, J. C. ^{[3
]}

Avanov, L. A. ^{[3
]}

Lavraud, B. ^{[10
,11
]}

Saito, Y. ^{[12
]}

Giles, B. L. ^{[3
]}

Pollock, C. J. ^{[3
]}

Burch, J. L. ^{[13
]}

机构：

[1] Swedish Inst Space Phys, Uppsala, Sweden

[2] Uppsala Univ, Dept Phys & Astron, Uppsala, Sweden

[3] NASA, Goddard Space Flight Ctr, Greenbelt, MD USA

[4] Univ Maryland, Dept Astron, College Pk, MD 20742 USA

[5] KTH Royal Inst Technol, Sch Elect Engn, Space & Plasma Phys, Stockholm, Sweden

[6] Univ Colorado, Lab Atmospher & Space Phys, Boulder, CO 80309 USA

[7] Austrian Acad Sci, Space Res Inst, Graz, Austria

[8] Univ Calif Los Angeles, Dept Earth & Space Sci, Los Angeles, CA USA

[9] Univ New Hampshire, Ctr Space Sci, Durham, NH 03824 USA

[10] Univ Toulouse, Inst Rech Astrophys & Planetol, Toulouse, France

[11] CNRS, UMR 5277, Toulouse, France

[12] Inst Space & Astronaut Sci, JAXA, Sagamihara, Kanagawa, Japan

[13] Southwest Res Inst, San Antonio, TX USA

来源：

GEOPHYSICAL RESEARCH LETTERS | 2016年 / 43卷 / 13期

关键词：

magnetic reconnection; electron demagnetization; finite gyroradius effects; electron diffusion region; DIFFUSION REGION;

D O I：

10.1002/2016GL069205

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

We present observations of asymmetric magnetic reconnection showing evidence of electron demagnetization in the electron outflow. The observations were made at the magnetopause by the four Magnetospheric Multiscale (MMS) spacecraft, separated by approximate to 15km. The reconnecting current sheet has negligible guide field, and all four spacecraft likely pass close to the electron diffusion region just south of the X line. In the electron outflow near the X line, all four spacecraft observe highly structured electron distributions in a region comparable to a few electron gyroradii. The distributions consist of a core with T-vertical bar>T and a nongyrotropic crescent perpendicular to the magnetic field. The crescents are associated with finite gyroradius effects of partly demagnetized electrons. These observations clearly demonstrate the manifestation of finite gyroradius effects in an electron-scale reconnection current sheet.

引用

页码：6724 / 6733

页数：10

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