Premium
Recirculation of energetic particles in Jupiter's magnetosphere
Author(s) -
Sentman D. D.,
Van Allen J. A.,
Goertz C. K.
Publication year - 1975
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/gl002i010p00465
Subject(s) - magnetosphere , physics , jovian , jupiter (rocket family) , pitch angle , equator , range (aeronautics) , van allen radiation belt , astrophysics , planet , geophysics , latitude , astronomy , plasma , nuclear physics , saturn , spacecraft , materials science , composite material
A significant new finding from analysis of Pioneer 11 observations in the magnetosphere of Jupiter is that there is net streaming of both electrons E e > 40 keV and E e > 560 keV and protons 0.6l < E p < 3.41 MeV away from the planet along high latitude field lines. This result is compatible with the recent suggestion of Nishida that energetic particles undergo trans‐L shell diffusion at low altitudes without significant change of energy. Our new finding coupled with his hypothesis and other considerations provides a plausible explanation for the remarkable pitch angle distributions near the equator in the range 12 < L < 25; the presence of particles of ≈ MeV energy at the outer edge of the magnetosphere; and hence, via conventional inward diffusion processes, the presence of those having magnetic moments of several hundred MeV per gauss in the inner magnetosphere. The recirculation of energetic particles emerges as an important dynamical feature of the Jovian magnetosphere. It is also suggested that emission of energetic particles into interplanetary space occurs at the polar caps rather than at the equator.