An explanation of auroral intensification during the substorm expansion phase
An explanation of auroral intensification during the substorm expansion phase
复制标题
亚暴扩展阶段极光增强的解释
DOI：
10.1002/2017ja024029
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发表时间：
2017-08
影响因子：
2.8
通讯作者：
Kalmoni N. M. E.
中科院分区：
文献类型：
--
作者：
Yao Zhonghua;Rae I. J.;Lui A. T. Y.;Murphy K. R.;Owen C. J.;Pu Z. Y.;Forsyth C.;Grodent D.;Zong Q. -G.;Du A. M.;Kalmoni N. M. E.
A multiple auroral onset substorm on 28 March 2010 provides an opportunity to understand the physical mechanism in generating auroral intensifications during a substorm expansion phase. Conjugate observations of magnetic fields and plasma from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft, of field‐aligned currents (FACs) from the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) satellites, and from ground‐based magnetometers and aurora are all available. The comprehensive measurements allow us to further our understanding of the complicated causalities among dipolarization, FAC generation, particle acceleration, and auroral intensification. During the substorm expansion phase, the plasma sheet expanded and was perturbed leading to the generation of a slow mode wave, which modulated electron flux in the outer plasma sheet. During this current sheet expansion, field‐aligned currents formed, and geomagnetic perturbations were simultaneously detected by ground‐based instruments. However, a magnetic dipolarization did not occur until about 3 min later in the outer plasma sheet observed by THEMIS‐A spacecraft (THA). We believe that this dipolarization led to an efficient Fermi acceleration to electrons and consequently the cause of a significant auroral intensification during the expansion phase as observed by the All‐Sky Imagers (ASIs). This Fermi acceleration mechanism operating efficiently in the outer plasma sheet during the expansion phase could be a common explanation of the poleward auroral development after substorm onset. These results also show a good agreement between the upward FAC derived from AMPERE measurements and the auroral brightening observed by the ASIs.
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影响因子：
8.6
作者：
R. Albert
通讯作者：
R. Albert
DOI：
10.1002/jgra.50419
发表时间：
2013-08
期刊：
Journal of Geophysical Research: Space Physics
影响因子：
--
作者：
Z. Yao;V. Angelopoulos;Z. Pu;S. Fu;M. Kubyshkina;J. Liu;X. Chu;T. Nishimura;X. Cao
通讯作者：
Z. Yao;V. Angelopoulos;Z. Pu;S. Fu;M. Kubyshkina;J. Liu;X. Chu;T. Nishimura;X. Cao
影响因子：
5.2
作者：
A. Walsh;C. Owen;A. Fazakerley;C. Forsyth;I. Dandouras
通讯作者：
A. Walsh;C. Owen;A. Fazakerley;C. Forsyth;I. Dandouras
影响因子：
8.6
作者：
G. Marklund;Soheil Sadeghi;T. Karlsson;P. Lindqvist;H. Nilsson;C. Forsyth;A. Fazakerley;E. Lucek-E.-Luce
通讯作者：
G. Marklund;Soheil Sadeghi;T. Karlsson;P. Lindqvist;H. Nilsson;C. Forsyth;A. Fazakerley;E. Lucek-E.-Luce
影响因子：
--
作者：
J. Craven;L. Frank
通讯作者：
J. Craven;L. Frank