Тип публикации: статья из журнала
Год издания: 1998
Идентификатор DOI: 10.1029/GM104p0297
Аннотация: On May 23, 1995, the Comprehensive Plasma Instrumentation (CPI) onboard the Geotail spacecraft observed a complex and structured ion distribution function near the magnetotail midplane atX ~ -10 RE. On the same day, the Wind spacecraft observed a very high density (~ 40 cm-3) solar wind and an interplanetary magnetic field (IMF) thПоказать полностьюat was predominantly northward but had several southward turnings. We have inferred the sources of the ions in this distribution function by following approximately 90,000 ion trajectories backward in time using time-dependent electric and magnetic fields obtained from a global MHD simulation. Wind data were used as input for the MHD model. We found that three sources contributed to this distribution: the ionosphere, the plasma mantle which had near-Earth and distant tail components, and the low latitude boundary layer (LLBL). Moreover, distinct structures in the low energy part of the distribution function were found to be associated with individual sources. Structures near 0° pitch angle were made up of either ionospheric or plasma mantle ions, while structures near 90° pitch angle were dominated by ions from the LLBL source. Particles that underwent nonadiabatic acceleration were numerous in the higher energy part of the ion distribution function, whereas ionospheric and LLBL ions were mosdy adiabatic. A large proportion of the near-Earth mantle ions underwent adiabatic acceleration, while most of the distant mantle ions experienced nonadiabatic acceleration.
Журнал: Geophysical Monograph Series
Выпуск журнала: Т. 104
Номера страниц: 297-312
ISSN журнала: 00658448