Submitting Campus
Daytona Beach
Department
Physical Sciences
Document Type
Article
Publication/Presentation Date
5-2017
Abstract/Description
Energetic ion distributions in the near-Earth plasma sheet can provide important information for understanding the entry of ions into the magnetosphere and their transportation, acceleration, and losses in the near-Earth region. In this study, 11 years of energetic proton and oxygen observations (> ~274 keV) from Cluster/Research with Adaptive Particle Imaging Detectors were used to statistically study the energetic ion distributions in the near-Earth region. The dawn-dusk asymmetries of the distributions in three different regions (dayside magnetosphere, near-Earth nightside plasma sheet, and tail plasma sheet) are examined in Northern and Southern Hemispheres. The results show that the energetic ion distributions are influenced by the dawn-dusk interplanetary magnetic field (IMF) direction. The enhancement of ion intensity largely correlates with the location of the magnetic reconnection at the magnetopause. The results imply that substorm-related acceleration processes in the magnetotail are not the only source of energetic ions in the dayside and the near-Earth magnetosphere. Energetic ions delivered through reconnection at the magnetopause significantly affect the energetic ion population in the magnetosphere. We also believe that the influence of the dawn-dusk IMF direction should not be neglected in models of the particle population in the magnetosphere.
Publication Title
Journal of Geophysical Research: Space Physics
DOI
https://doi.org/10.1002/2016JA023471
Publisher
American Geophysical Union
Grant or Award Name
RAPID instrument at MPS under grant 50 OC 1602, NASA grant 15-HGI15_2-0187
Scholarly Commons Citation
Luo, H., E. A. Kronberg, K. Nykyri, K. J. Trattner, P. W. Daly, G. X. Chen, A. M. Du, and Y. S. Ge (2017), IMF dependence of energetic oxygen and hydrogen ion distributions in the near-Earth magnetosphere, J. Geophys. Res. Space Physics, 122, 5168–5180, doi:10.1002/2016JA023471