Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration
Van Allen Probes in situ observations are used to examine detailed subpacket structure observed in strong VLF (very low frequency) rising-tone chorus elements observed at the time of a rapid MeV electron energization in the inner magnetosphere. Analysis of the frequency gap between lower and upper c...
| Main Authors: | , , |
|---|---|
| 其他作者: | |
| 格式: | 文件 |
| 出版: |
Springer Science and Business Media LLC
2021
|
| 在线阅读: | https://hdl.handle.net/1721.1/131071 |
| _version_ | 1826206122476830720 |
|---|---|
| author | Foster, John C Erickson, Philip J Omura, Yoshiharu |
| author2 | Haystack Observatory |
| author_facet | Haystack Observatory Foster, John C Erickson, Philip J Omura, Yoshiharu |
| author_sort | Foster, John C |
| collection | MIT |
| description | Van Allen Probes in situ observations are used to examine detailed subpacket structure observed in strong VLF (very low frequency) rising-tone chorus elements observed at the time of a rapid MeV electron energization in the inner magnetosphere. Analysis of the frequency gap between lower and upper chorus-band waves identifies f[subscript ceEQ], the electron gyrofrequency in the equatorial wave generation region. Initial subpackets in these strong chorus rising-tone elements begin at a frequency near 1/4 f[subscript ceEQ] and exhibit smooth gradual frequency increase across their > 10 ms temporal duration. A second much stronger subpacket is seen at frequencies around the local value of 1/4f[subscript ce] with small wave normal angle (< 10°) and steeply rising df/dt. Smooth frequency and phase variation across and between the initial subpackets support continuous phase trapping of resonant electrons and increased potential for MeV electron acceleration. The total energy gain for individual seed electrons with energies between 100 keV and 3 MeV ranges between 2 and 15%, in their nonlinear interaction with a single chorus element. |
| first_indexed | 2024-09-23T13:24:26Z |
| format | Article |
| id | mit-1721.1/131071 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T13:24:26Z |
| publishDate | 2021 |
| publisher | Springer Science and Business Media LLC |
| record_format | dspace |
| spelling | mit-1721.1/1310712022-09-28T13:58:03Z Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration Foster, John C Erickson, Philip J Omura, Yoshiharu Haystack Observatory Van Allen Probes in situ observations are used to examine detailed subpacket structure observed in strong VLF (very low frequency) rising-tone chorus elements observed at the time of a rapid MeV electron energization in the inner magnetosphere. Analysis of the frequency gap between lower and upper chorus-band waves identifies f[subscript ceEQ], the electron gyrofrequency in the equatorial wave generation region. Initial subpackets in these strong chorus rising-tone elements begin at a frequency near 1/4 f[subscript ceEQ] and exhibit smooth gradual frequency increase across their > 10 ms temporal duration. A second much stronger subpacket is seen at frequencies around the local value of 1/4f[subscript ce] with small wave normal angle (< 10°) and steeply rising df/dt. Smooth frequency and phase variation across and between the initial subpackets support continuous phase trapping of resonant electrons and increased potential for MeV electron acceleration. The total energy gain for individual seed electrons with energies between 100 keV and 3 MeV ranges between 2 and 15%, in their nonlinear interaction with a single chorus element. NASA (Contract NAS5‐01072) 2021-07-13T15:36:02Z 2021-07-13T15:36:02Z 2021-07 2021-02 Article http://purl.org/eprint/type/JournalArticle 1880-5981 https://hdl.handle.net/1721.1/131071 Foster, John C. et al. "Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration." Earth, Planets, and Space 73, 1 (July 2021): 140. © 2021 The Author(s) http://dx.doi.org/10.1186/s40623-021-01467-4 Earth, Planets, and Space Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf Springer Science and Business Media LLC John Foster |
| spellingShingle | Foster, John C Erickson, Philip J Omura, Yoshiharu Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration |
| title | Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration |
| title_full | Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration |
| title_fullStr | Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration |
| title_full_unstemmed | Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration |
| title_short | Subpacket structure in strong VLF chorus rising tones: characteristics and consequences for relativistic electron acceleration |
| title_sort | subpacket structure in strong vlf chorus rising tones characteristics and consequences for relativistic electron acceleration |
| url | https://hdl.handle.net/1721.1/131071 |
| work_keys_str_mv | AT fosterjohnc subpacketstructureinstrongvlfchorusrisingtonescharacteristicsandconsequencesforrelativisticelectronacceleration AT ericksonphilipj subpacketstructureinstrongvlfchorusrisingtonescharacteristicsandconsequencesforrelativisticelectronacceleration AT omurayoshiharu subpacketstructureinstrongvlfchorusrisingtonescharacteristicsandconsequencesforrelativisticelectronacceleration |