Direct Evidence of Electron Acceleration at the Dipolarization Front
The dramatic changes in the magnetic field at the dipolarization front (DF) provide a suitable environment for electron acceleration, which usually can cause the flux enhancement of energetic electrons behind the front. However, it is unknown whether energetic electrons observed at the DF are energi...
| Main Authors: | , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal |
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| Online Access: | https://doi.org/10.3847/1538-4357/acd1dd |
| _version_ | 1797694122994171904 |
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| author | Y. Y. Wei S. Y. Huang K. Jiang Z. G. Yuan S. B. Xu J. Zhang Q. Y. Xiong Z. Wang R. T. Lin L. Yu Y. Y. Li C. M. Wang G. J. Song |
| author_facet | Y. Y. Wei S. Y. Huang K. Jiang Z. G. Yuan S. B. Xu J. Zhang Q. Y. Xiong Z. Wang R. T. Lin L. Yu Y. Y. Li C. M. Wang G. J. Song |
| author_sort | Y. Y. Wei |
| collection | DOAJ |
| description | The dramatic changes in the magnetic field at the dipolarization front (DF) provide a suitable environment for electron acceleration, which usually can cause the flux enhancement of energetic electrons behind the front. However, it is unknown whether energetic electrons observed at the DF are energized locally, and which mechanism accelerates the electrons at the DF is unclear. Our study performs a direct quantitative analysis to reveal the acceleration process of energetic electrons at the DF using the high-time-resolution data from NASA's Magnetospheric Multiscale mission. The fluxes of energetic electrons at 90° are enhanced at the front. Under adiabatic conditions, our quantitative analysis indicates that these electrons at the front could be locally accelerated to over 100 keV by betatron acceleration. Eventually, the electron temperature anisotropy formed via the betatron mechanism could provide the free energy to excite whistler waves at the DF. Our quantitative study provides, for the first time, strong direct evidence for the local electron acceleration at the DF. |
| first_indexed | 2024-03-12T02:53:22Z |
| format | Article |
| id | doaj.art-a0a625e078bf442789d6975ef8106e3a |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-12T02:53:22Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal |
| spelling | doaj.art-a0a625e078bf442789d6975ef8106e3a2023-09-03T15:27:33ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-01950211210.3847/1538-4357/acd1ddDirect Evidence of Electron Acceleration at the Dipolarization FrontY. Y. Wei0https://orcid.org/0000-0003-1199-5229S. Y. Huang1https://orcid.org/0000-0002-3595-2525K. Jiang2https://orcid.org/0000-0001-7889-0507Z. G. Yuan3S. B. Xu4J. Zhang5https://orcid.org/0000-0001-5111-2609Q. Y. Xiong6https://orcid.org/0000-0003-1840-3281Z. Wang7R. T. Lin8https://orcid.org/0000-0003-4012-9418L. Yu9Y. Y. Li10C. M. Wang11G. J. Song12School of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnSchool of Electronic Information, Hubei Luojia Laboratory, Wuhan University , Wuhan, 430072, People’s Republic of China ; shiyonghuang@whu.edu.cnThe dramatic changes in the magnetic field at the dipolarization front (DF) provide a suitable environment for electron acceleration, which usually can cause the flux enhancement of energetic electrons behind the front. However, it is unknown whether energetic electrons observed at the DF are energized locally, and which mechanism accelerates the electrons at the DF is unclear. Our study performs a direct quantitative analysis to reveal the acceleration process of energetic electrons at the DF using the high-time-resolution data from NASA's Magnetospheric Multiscale mission. The fluxes of energetic electrons at 90° are enhanced at the front. Under adiabatic conditions, our quantitative analysis indicates that these electrons at the front could be locally accelerated to over 100 keV by betatron acceleration. Eventually, the electron temperature anisotropy formed via the betatron mechanism could provide the free energy to excite whistler waves at the DF. Our quantitative study provides, for the first time, strong direct evidence for the local electron acceleration at the DF.https://doi.org/10.3847/1538-4357/acd1ddPlanetary magnetospheresSpace plasmasPlasma physicsPlasma jets |
| spellingShingle | Y. Y. Wei S. Y. Huang K. Jiang Z. G. Yuan S. B. Xu J. Zhang Q. Y. Xiong Z. Wang R. T. Lin L. Yu Y. Y. Li C. M. Wang G. J. Song Direct Evidence of Electron Acceleration at the Dipolarization Front The Astrophysical Journal Planetary magnetospheres Space plasmas Plasma physics Plasma jets |
| title | Direct Evidence of Electron Acceleration at the Dipolarization Front |
| title_full | Direct Evidence of Electron Acceleration at the Dipolarization Front |
| title_fullStr | Direct Evidence of Electron Acceleration at the Dipolarization Front |
| title_full_unstemmed | Direct Evidence of Electron Acceleration at the Dipolarization Front |
| title_short | Direct Evidence of Electron Acceleration at the Dipolarization Front |
| title_sort | direct evidence of electron acceleration at the dipolarization front |
| topic | Planetary magnetospheres Space plasmas Plasma physics Plasma jets |
| url | https://doi.org/10.3847/1538-4357/acd1dd |
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