Open AccessFormation of the mass density peak at the magnetospheric equator triggered by EMIC waves
Author(s) -
Xue ZuXiang,
Yuan ZhiGang,
Yu XiongDong,
ShiYong Huang,
Qiao Zheng
Publication year - 2021
Publication title -
earth and planetary physics
Language(s) - English
Resource type - Journals
ISSN - 2096-3955
DOI - 10.26464/epp2021008
Subject(s) - equator , physics , ion , emic and etic , cyclotron , perpendicular , atomic physics , geophysics , computational physics , latitude , astronomy , geometry , mathematics , quantum mechanics , sociology , anthropology
We report a simultaneous observation of two band electromagnetic ion cyclotron (EMIC) waves and toroidal Alfvén waves by the Van Allen Probe mission. Through wave frequency analyses, the mass density ρ is found to be locally peaked at the magnetic equator. Perpendicular fluxes of ions (< 100 eV) increase simultaneously with the appearances of EMIC waves, indicating a heating of these ions by EMIC waves. In addition, the measured ion distributions also support the equatorial peak formation, which accords with the result of the frequency analyses. The formation of local mass density peaks at the equator should be due to enhancements of equatorial ion concentrations, which are triggered by EMIC waves’ perpendicular heating on low energy ions.