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A comprehensive model of ion diffusion and charge exchange in the cold Io torusA comprehensive analytic model of radial diffusion in the cold Io torus is developed. The model involves a generalized molecular cloud theory of SO2 and its dissociation fragments SO, O2, S, and O, which are formed at a relatively large rate by solar UV photodissociation of SO2. The key component of the new theory is SO, which can react with S(+) through a near-resonant charge exchange process that is exothermic. This provides a mechanism for the rapid depletion of singly ionized sulfur in the cold torus and can account for the large decrease in the total flux tube content inward of Io's orbit. The model is used to demonstrate quantitatively the effects of radial diffusion in a charge exchange environment that acts as a combined source and sink for ions in various charge states. A detailed quantitative explanation for the O(2+) component of the cold torus is given, and insight is derived into the workings of the so-called plasma 'ribbon'.
Document ID
19880038652
Document Type
Reprint (Version printed in journal)
Authors
Barbosa, D. D. (California Univ. Los Angeles, CA, United States)
Moreno, M. A. (California, University Los Angeles, United States)
Date Acquired
August 13, 2013
Publication Date
February 1, 1988
Publication Information
Publication: Journal of Geophysical Research
Volume: 93
ISSN: 0148-0227
Subject Category
LUNAR AND PLANETARY EXPLORATION
Funding Number(s)
CONTRACT_GRANT: NGL-05-007-190
CONTRACT_GRANT: NSF ATM-86-06857
Distribution Limits
Public
Copyright
Other