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

来源：

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS | 2019年 / 124卷 / 12期

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

页码：10153 / 10169

页数：17

共 76 条

[1] Differing Properties of Two Ion-Scale Magnetopause Flux Ropes [J].

Alm, L. ;

Farrugia, C. J. ;

Paulson, K. W. ;

Argall, M. R. ;

Torbert, R. B. ;

Burch, J. L. ;

Ergun, R. E. ;

Russell, C. T. ;

Strangeway, R. J. ;

Khotyaintsev, Y. V. ;

Lindqvist, P. -A. ;

Marklund, G. T. ;

Giles, B. L. .

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2018, 123 (01) :114-131

[2] New Features of Electron Phase Space Holes Observed by the THEMIS Mission [J].

Andersson, L. ;

Ergun, R. E. ;

Tao, J. ;

Roux, A. ;

LeContel, O. ;

Angelopoulos, V. ;

Bonnell, J. ;

McFadden, J. P. ;

Larson, D. E. ;

Eriksson, S. ;

Johansson, T. ;

Cully, C. M. ;

Newman, D. N. ;

Goldman, M. V. ;

Glassmeier, K. -H. ;

Baumjohann, W. .

PHYSICAL REVIEW LETTERS, 2009, 102 (22)

[3] Magnetospheric Multiscale Overview and Science Objectives [J].

Burch, J. L. ;

Moore, T. E. ;

Torbert, R. B. ;

Giles, B. L. .

SPACE SCIENCE REVIEWS, 2016, 199 (1-4) :5-21

[4] Electron-scale measurements of magnetic reconnection in space [J].

Burch, J. L. ;

Torbert, R. B. ;

Phan, T. D. ;

Chen, L. -J. ;

Moore, T. E. ;

Ergun, R. E. ;

Eastwood, J. P. ;

Gershman, D. J. ;

Cassak, P. A. ;

Argall, M. R. ;

Wang, S. ;

Hesse, M. ;

Pollock, C. J. ;

Giles, B. L. ;

Nakamura, R. ;

Mauk, B. H. ;

Fuselier, S. A. ;

Russell, C. T. ;

Strangeway, R. J. ;

Drake, J. F. ;

Shay, M. A. ;

Khotyaintsev, Yu. V. ;

Lindqvist, P. -A. ;

Marklund, G. ;

Wilder, F. D. ;

Young, D. T. ;

Torkar, K. ;

Goldstein, J. ;

Dorelli, J. C. ;

Avanov, L. A. ;

Oka, M. ;

Baker, D. N. ;

Jaynes, A. N. ;

Goodrich, K. A. ;

Cohen, I. J. ;

Turner, D. L. ;

Fennell, J. F. ;

Blake, J. B. ;

Clemmons, J. ;

Goldman, M. ;

Newman, D. ;

Petrinec, S. M. ;

Trattner, K. J. ;

Lavraud, B. ;

Reiff, P. H. ;

Baumjohann, W. ;

Magnes, W. ;

Steller, M. ;

Lewis, W. ;

Saito, Y. .

SCIENCE, 2016, 352 (6290)

[5] Scaling of asymmetric magnetic reconnection: General theory and collisional simulations [J].

Cassak, P. A. ;

Shay, M. A. .

PHYSICS OF PLASMAS, 2007, 14 (10)

[6] Scaling of Sweet-Parker reconnection with secondary islands [J].

Cassak, P. A. ;

Shay, M. A. ;

Drake, J. F. .

PHYSICS OF PLASMAS, 2009, 16 (12)

[7]

Daughton W, 2011, NAT PHYS, V7, P539, DOI [10.1038/NPHYS1965, 10.1038/nphys1965]

[8] Electromagnetic properties of the lower-hybrid drift instability in a thin current sheet [J].

Daughton, W .

PHYSICS OF PLASMAS, 2003, 10 (08) :3103-3119

[9] Transition from collisional to kinetic regimes in large-scale reconnection layers [J].

Daughton, W. ;

Roytershteyn, V. ;

Albright, B. J. ;

Karimabadi, H. ;

Yin, L. ;

Bowers, Kevin J. .

PHYSICAL REVIEW LETTERS, 2009, 103 (06)

[10] Fully kinetic simulations of undriven magnetic reconnection with open boundary conditions [J].

Daughton, William ;

Scudder, Jack ;

Karimabadi, Homa .

PHYSICS OF PLASMAS, 2006, 13 (07)

← 1 2 3 4 5 6 7 8 →