Open AccessModeling global O+ substorm injection using analytic magnetic field model
Author(s) -
Jones S. T.,
Fok M.C.,
Brandt P. C.
Publication year - 2006
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2006ja011607
Subject(s) - substorm , geophysics , field (mathematics) , magnetic field , geology , physics , geodesy , magnetosphere , mathematics , quantum mechanics , pure mathematics
During storm‐time substorms the IMAGE/High‐Energy Neutral Atom (HENA) global magnetospheric plasma imager observes dramatic rise and fall of the oxygen energetic neutral atom (ENA) fluxes in the 29–180 keV range that are well correlated with substorm onsets. The corresponding hydrogen ENA flux (10–198 keV) shows a much more gradual rise and fall. We use a three‐dimensional test particle code in time varying electric and magnetic fields to study mechanisms causing the dramatic oxygen variation. Consistent with our previous work, we find that nonadiabatic heating occurs during the dipolarization of the geomagnetic field. The simulation model reproduces key features including the high‐altitude increase of the ENA flux and enhancement timescale.