Coupled quasi-linear wave damping and stochastic acceleration of pickup ions in the solar wind

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JA02096· OSTI ID:5261543

Bogdan, T J ^[1]; Lee, M A ^[2]; Schneider, P ^[3]

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1. National Center for Atmospheric Research, Boulder, CO (USA)
2. Univ. of New Hampshire, Durham (USA)
3. Institut fuer Astrophysik, Garching bei Muenchen (Germany)

Coupled spatially homogeneous quasilinear kinetic equations are derived which describe the evolution of the energetic ion omnidirectional distribution function and the intensities of magnetohydrodynamic waves propagating parallel and antiparallel to the ambient magnetic field. For application to pickup ions the equations may also include an energetic ion injection rate and wave excitation or damping caused by isotropization of the newborn ions. The wave kinetic equations may be integrated to yield explicit expressions for the wave intensities, which may be substituted into the ion kinetic equations to yield a single self-consistent energy diffusion equation for the energetic ions. The theory represents the first treatment of stochastic (second-order Fermi) acceleration in which the back reaction of the ions on the turbulence is included self-consistently. Numerical solutions of the kinetic equations are presented for four cases of pickup ions in the solar wind which illustrate the essential features of the evolution: (1) interstellar pickup helium near a heliocentric radial distance of 1 AU; (2) interstellar pickup hydrogen near 10 AU; (3) water group pickup ions downstream of the bow wave of Comet Giacobini-Zinner for parameters observed during the International Cometary Explorer flyby; (4) water group pickup ions downstream of the bow wave of Comet Halley for parameters observed during the Giotto flyby. Wave damping is small at comet G-Z, and the calculated energy spectra do not appear to be in quantitative agreement with the observed spectra (Richardson et al., 1987). At Comet Halley, on the other hand, wave damping is substantial and the calculated spectra appear to be in general agreement with the observations (McKenna-Lawlor et al. 1989).

• OSTI ID: 5261543
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 96:A1; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
640107 -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELERATION
CHARGED PARTICLES
COMETS
DAMPING
DIFFUSION
DISTRIBUTION FUNCTIONS
EQUATIONS
FUNCTIONS
HELIUM IONS
HYDROGEN COMPOUNDS
HYDROGEN IONS
HYDROMAGNETIC WAVES
INTERACTIONS
INTERSTELLAR SPACE
IONIC COMPOSITION
IONS
ISOTROPY
KINETIC EQUATIONS
MOLECULAR IONS
NUMERICAL SOLUTION
OXYGEN COMPOUNDS
QUASILINEAR PROBLEMS
SOLAR ACTIVITY
SOLAR WIND
SPACE
STOCHASTIC PROCESSES
WATER
WAVE PROPAGATION