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Title: Multiple-Satellite Observation of Magnetic Dip Event During the Substorm on 10 October 2013

Abstract

Here, we present a multiple-satellite observation of the magnetic dip event during the substorm on 10 October 2013. The observation illustrates the temporal and spatial evolution of the magnetic dip and gives a compelling evidence that ring current ions induce the magnetic dip by enhanced plasma beta. The dip moves with the energetic ions in a comparable drift velocity and affects the dynamics of relativistic electrons in the radiation belt. In addition, the magnetic dip provides a favorable condition for the electromagnetic ion cyclotron (EMIC) wave generation based on the linear theory analysis. The calculated proton diffusion coefficients show that the observed EMIC wave can lead to the pitch angle scattering losses of the ring current ions, which in turn partially relax the magnetic dip in the observations. This study enriches our understanding of magnetic dip evolution and demonstrates the important role of the magnetic dip for the coupling of radiation belt and ring current.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [2]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4];  [4];  [5]
  1. Harbin Institute of Technology Shenzhen Graduate School, Shenzhen (China); Univ. of Science and Technology of China, Hefei (China); Univ. of Texas at Dallas, Richardson, TX (United States)
  2. Univ. of Texas at Dallas, Richardson, TX (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. Peking Univ., Beijing (China)
  5. Harbin Institute of Technology Shenzhen Graduate School, Shenzhen (China)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
National Aeronautic and Space Administration (NASA); USDOE
OSTI Identifier:
1415429
Report Number(s):
LA-UR-17-30359
Journal ID: ISSN 0094-8276
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Geophysical Research Letters
Additional Journal Information:
Journal Volume: 44; Journal Issue: 18; Journal ID: ISSN 0094-8276
Publisher:
American Geophysical Union
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; Heliospheric and Magnetospheric Physics; magnetic dip; ring current ions; radiation belt electrons; EMIC wave

Citation Formats

He, Zhaoguo, Chen, Lunjin, Zhu, Hui, Xia, Zhiyang, Reeves, Geoffrey D., Xiong, Ying, Xie, Lun, and Cao, Yong. Multiple-Satellite Observation of Magnetic Dip Event During the Substorm on 10 October 2013. United States: N. p., 2017. Web. doi:10.1002/2017GL074869.
He, Zhaoguo, Chen, Lunjin, Zhu, Hui, Xia, Zhiyang, Reeves, Geoffrey D., Xiong, Ying, Xie, Lun, & Cao, Yong. Multiple-Satellite Observation of Magnetic Dip Event During the Substorm on 10 October 2013. United States. doi:10.1002/2017GL074869.
He, Zhaoguo, Chen, Lunjin, Zhu, Hui, Xia, Zhiyang, Reeves, Geoffrey D., Xiong, Ying, Xie, Lun, and Cao, Yong. 2017. "Multiple-Satellite Observation of Magnetic Dip Event During the Substorm on 10 October 2013". United States. doi:10.1002/2017GL074869.
@article{osti_1415429,
title = {Multiple-Satellite Observation of Magnetic Dip Event During the Substorm on 10 October 2013},
author = {He, Zhaoguo and Chen, Lunjin and Zhu, Hui and Xia, Zhiyang and Reeves, Geoffrey D. and Xiong, Ying and Xie, Lun and Cao, Yong},
abstractNote = {Here, we present a multiple-satellite observation of the magnetic dip event during the substorm on 10 October 2013. The observation illustrates the temporal and spatial evolution of the magnetic dip and gives a compelling evidence that ring current ions induce the magnetic dip by enhanced plasma beta. The dip moves with the energetic ions in a comparable drift velocity and affects the dynamics of relativistic electrons in the radiation belt. In addition, the magnetic dip provides a favorable condition for the electromagnetic ion cyclotron (EMIC) wave generation based on the linear theory analysis. The calculated proton diffusion coefficients show that the observed EMIC wave can lead to the pitch angle scattering losses of the ring current ions, which in turn partially relax the magnetic dip in the observations. This study enriches our understanding of magnetic dip evolution and demonstrates the important role of the magnetic dip for the coupling of radiation belt and ring current.},
doi = {10.1002/2017GL074869},
journal = {Geophysical Research Letters},
number = 18,
volume = 44,
place = {United States},
year = 2017,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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