Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation

	Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation
	Lu, S.; Lin, Y.; Lu, Q. M.; Wang, X. Y.; Wang, R. S.; Huang, C.; Wu, M. Y.; Wang, S.
刊名	PHYSICS OF PLASMAS
	2015
卷号	22 期号:5 页码:52901
ISSN号	1070-664X
通讯作者	Lu, QM (reprint author), Univ Sci & Technol China, Dept Geophys & Planetary Sci, CAS Key Lab Geospace Environm, Hefei 230026, Peoples R China.
英文摘要	Flux ropes in the Earth's magnetotail are widely believed to play a crucial role in energy transport during substorms and the generation of energetic particles. Previous kinetic simulations are limited to the local-scale regime, and thus cannot be used to study the structure associated with the geomagnetic field and the global-scale evolution of the flux ropes. Here, the evolution of flux ropes in the magnetotail under a steady southward interplanetary magnetic field are studied with a newly developed three-dimensional global hybrid simulation model for dynamics ranging from the ion Larmor radius to the global convection time scales. Magnetic reconnection with multiple X-lines is found to take place in the near-tail current sheet at geocentric solar magneto-spheric distances x = -30R(E) similar to -15R(E) around the equatorial plane (z = 0). The magnetotail reconnection layer is turbulent, with a nonuniform structure and unsteady evolution, and exhibits properties of typical collisionless fast reconnection with the Hall effect. A number of small-scale flux ropes are generated through the multiple X-line reconnection. The diameter of the flux ropes is several R-E, and the spatial scale of the flux ropes in the dawn-dusk direction is on the order of several R-E and does not extend across the entire section of the magnetotail, contrary to previous models and MHD simulation results and showing the importance of the three-dimensional effects. The nonuniform and unsteady multiple X-line reconnection with particle kinetic effects leads to various kinds of flux rope evolution: The small-scale flux ropes propagate earthward or tailward after formation, and eventually merge into the near-Earth region or the mid-/distant-tail plasmoid, respectively. During the propagation, some of the flux ropes can be tilted in the geocentric solar magnetospheric (x, y) plane with respect to the y (dawn-dusk) axis. Coalescence between flux ropes is also observed. At the same time, the evolution of the flux ropes in the multiple X-line reconnection layer can also lead to the acceleration and heating of ions. (C) 2015 AIP Publishing LLC.
收录类别	SCI ; EI
语种	英语
内容类型	期刊论文
源URL	[http://ir.nssc.ac.cn/handle/122/4596]
专题	国家空间科学中心_空间科学部
推荐引用方式 GB/T 7714	Lu, S.,Lin, Y.,Lu, Q. M.,et al. Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation[J]. PHYSICS OF PLASMAS,2015,22(5):52901.
APA	Lu, S..,Lin, Y..,Lu, Q. M..,Wang, X. Y..,Wang, R. S..,...&Wang, S..(2015).Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation.PHYSICS OF PLASMAS,22(5),52901.
MLA	Lu, S.,et al."Evolution of flux ropes in the magnetotail: A three-dimensional global hybrid simulation".PHYSICS OF PLASMAS 22.5(2015):52901.