A Bifurcated Reconnecting Current Sheet in the Turbulent Magnetosheath

被引：0

作者：

Wang, Shimou ^{[1
,2
,3
]}

Wang, Rongsheng ^{[1
,2
,3
]}

Huang, Kai ^{[4
,5
]}

Guo, Jin ^{[1
,2
,3
]}

机构：

[1] Univ Sci & Technol China, Sch Earth & Space Sci, Deep Space Explorat Lab, Hefei 230026, Peoples R China

[2] Univ Sci & Technol China, CAS Ctr Excellence Comparat Planetol, CAS Key Lab Geospace Environm, Anhui Mengcheng Natl Geophys Observ, Hefei 230026, Peoples R China

[3] Collaborat Innovat Ctr Astronaut Sci & Technol, Harbin 150000, Peoples R China

[4] Harbin Inst Technol, Sch Phys, Harbin 150001, Peoples R China

[5] Harbin Inst Technol, Lab Space Environm & Phys Sci, Harbin 150001, Peoples R China

来源：

MAGNETOCHEMISTRY | 2024年 / 10卷 / 11期

基金：

中国博士后科学基金; 美国国家科学基金会;

关键词：

magnetic reconnection; magnetosheath; turbulence; current sheet; diffusion region; magnetic flux rope; MAGNETIC RECONNECTION; FIELD; INTERPLANETARY; SIGNATURES; ISLANDS;

D O I：

10.3390/magnetochemistry10110089

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

We report the Magnetospheric Multiscale (MMS) observation of a bifurcated reconnecting current sheet in Earth's dayside magnetosheath. Typical signatures of the ion diffusion region, including sub-Alfv & eacute;nic demagnetized ion outflow, super-Alfv & eacute;nic electron flows, Hall magnetic fields, electron heating, and energy dissipation, were found when MMS traversed the current sheet. The weak ion exhaust at the current sheet center was bounded by two current peaks in which super-Alfv & eacute;nic electron flow directed toward and away from the X line were observed, respectively. Both off-center current peaks were primarily carried by electrons, one of which was supported by field-aligned current, while the other was mainly supported by current driven by electric field drift. The two current peaks also exhibit other differences, including electron heating, electron pitch angle distributions, electron nongyrotropy, energy dissipation, and magnetic field curvature. An ion-scale magnetic flux rope was detected between the two current peaks where electrons showed field-aligned bidirectional distribution, in contrast to field-aligned distribution parallel to the magnetic field in two current peaks. The observed current sheet was embedded in a background shear flow. This shear flow worked together with the guide field and asymmetric field and density to affect the electron dynamics. Our results reveal the reconnection properties in this special plasma and field regime which may be common in turbulent environments.

引用

页数：12

共 93 条

[1] Current sheet structure around the near-Earth neutral line observed by Geotail [J].

Asano, Y ;

Mukai, T ;

Hoshino, M ;

Saito, Y ;

Hayakawa, H ;

Nagai, T .

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2004, 109 (A2)

[2] 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

[3] 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)

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

Cassak, P. A. ;

Shay, M. A. .

PHYSICS OF PLASMAS, 2007, 14 (10)

[5] Electron Heating at Kinetic Scales in Magnetosheath Turbulence [J].

Chasapis, Alexandros ;

Matthaeus, W. H. ;

Parashar, T. N. ;

LeContel, O. ;

Retino, A. ;

Breuillard, H. ;

Khotyaintsev, Y. ;

Vaivads, A. ;

Lavraud, B. ;

Eriksson, E. ;

Moore, T. E. ;

Burch, J. L. ;

Torbert, R. B. ;

Lindqvist, P. -A. ;

Ergun, R. E. ;

Marklund, G. ;

Goodrich, K. A. ;

Wilder, F. D. ;

Chutter, M. ;

Needell, J. ;

Rau, D. ;

Dors, I. ;

Russell, C. T. ;

Le, G. ;

Magnes, W. ;

Strangeway, R. J. ;

Bromund, K. R. ;

Leinweber, H. K. ;

Plaschke, F. ;

Fischer, D. ;

Anderson, B. J. ;

Pollock, C. J. ;

Giles, B. L. ;

Paterson, W. R. ;

Dorelli, J. ;

Gershman, D. J. ;

Avanov, L. ;

Saito, Y. .

ASTROPHYSICAL JOURNAL, 2017, 836 (02)

[6] Electron diffusion region during magnetopause reconnection with an intermediate guide field: Magnetospheric multiscale observations [J].

Chen, L. -J. ;

Hesse, M. ;

Wang, S. ;

Gershman, D. ;

Ergun, R. E. ;

Burch, J. ;

Bessho, N. ;

Torbert, R. B. ;

Giles, B. ;

Webster, J. ;

Pollock, C. ;

Dorelli, J. ;

Moore, T. ;

Paterson, W. ;

Lavraud, B. ;

Strangeway, R. ;

Russell, C. ;

Khotyaintsev, Y. ;

Lindqvist, P. -A. ;

Avanov, L. .

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2017, 122 (05) :5235-5246

[7] Magnetic Nulls in the Reconnection Driven by Turbulence [J].

Chen, X. H. ;

Fu, H. S. ;

Liu, C. M. ;

Cao, D. ;

Wang, Z. ;

Dunlop, M. W. ;

Chen, Z. Z. ;

Peng, F. Z. .

ASTROPHYSICAL JOURNAL, 2018, 852 (01)

[8] First Observation of Magnetic Flux Rope Inside Electron Diffusion Region [J].

Chen, Z. Z. ;

Fu, H. S. ;

Wang, Z. ;

Guo, Z. Z. ;

Xu, Y. ;

Liu, C. M. .

GEOPHYSICAL RESEARCH LETTERS, 2021, 48 (07)

[9] Global-scale magnetosphere convection driven by dayside magnetic reconnection [J].

Dai, Lei ;

Zhu, Minghui ;

Ren, Yong ;

Gonzalez, Walter ;

Wang, Chi ;

Sibeck, David ;

Samsonov, Andrey ;

Escoubet, Philippe ;

Tang, Binbin ;

Zhang, Jiaojiao ;

Branduardi-Raymont, Graziella .

NATURE COMMUNICATIONS, 2024, 15 (01)

[10]

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

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