Ionosphere-exosphere coupling through charge exchange and momentum transfer in hydrogen-proton collisions

Journal Article · Wed May 01 04:00:00 EDT 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JA02744· OSTI ID:5316307

Hodges, Jr, R R; Breig, E L ^[1]

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1. Univ. of Texas, Richardson, TX (USA)

The authors examine the implications of a traditional assumption of exospheric physics, that collisions of hydrogen atoms and protons preferentially result in charge exchange with negligible momentum transfer. Initially adopted as a necessary convenience to accommodate limited computer resources in exosphere model calculations, this approximation results in a direct transformation of the proton velocity distribution into a hot component of neutral hydrogen. It leads to significant enhancements in both escape and in the formation of extended planetary coronae. With expanding computational facilities, the need for the approximation has passed. As the first step toward its replacement with a realistic, quantum mechanical model of the H-H{sup +} collision process, they calculate differential and cumulative cross sections for quantum elastic scattering of indistinguishable nuclei for a fine grid of encounter energies and scattering angles. These data are used to study the nature of ionosphere-exosphere coupling through H-H{sup +} collisions, and to demonstrate that the distribution of velocities of scattered H produced in the traditional exospheric charge exchange approximation, as well as that arising from an alternative, fluid dynamics approach, leads to unacceptable abundances of coronal atoms in long-term, highly elliptic trajectories.

• OSTI ID: 5316307
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 96:A5; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640200* -- Atmospheric Physics
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
ATMOSPHERIC CHEMISTRY
ATOM COLLISIONS
CATIONS
CHARGE EXCHANGE
CHARGED PARTICLES
CHEMICAL COMPOSITION
CHEMISTRY
COLLISIONS
EARTH ATMOSPHERE
ELASTIC SCATTERING
ELEMENT ABUNDANCE
ELEMENTS
EXOSPHERE
HYDROGEN
HYDROGEN IONS
HYDROGEN IONS 1 PLUS
INTERACTIONS
ION COLLISIONS
ION-ATOM COLLISIONS
IONOSPHERE
IONS
MATHEMATICAL MODELS
MECHANICS
MOMENTUM TRANSFER
NONMETALS
PLANETARY IONOSPHERES
QUANTUM MECHANICS
SCATTERING