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Physical Sciences and Mathematics Commons

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Astrophysics and Astronomy

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Florida Institute of Technology

2003

Diffusion

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Perpendicular Transport Of Solar Energetic Particles In Heliospheric Magnetic Fields, Ming Zhang, Jack Randy Jokipii, Robert Bruce Mckibben Sep 2003

Perpendicular Transport Of Solar Energetic Particles In Heliospheric Magnetic Fields, Ming Zhang, Jack Randy Jokipii, Robert Bruce Mckibben

Aerospace, Physics, and Space Science Faculty Publications

This paper presents direct observational evidence for large perpendicular diffusive flows of solar energetic particles in heliospheric magnetic fields. Using anisotropy measurements of 40-92 MeV protons obtained by the High-Energy Telescope of the COSPIN consortium on Ulysses at high heliographic latitudes, we find that during several gradual solar particle events, for periods of many hours, the observed particle flow is directed at significant angles to the measured local magnetic field direction, which can only be explained by cross-field diffusion. The variation of the particle flow direction with the magnetic field direction seen in the 2000 July 14 solar energetic particle …


Nonlinear Collisionless Perpendicular Diffusion Of Charged Particles, William H. Matthaeus, Gang Qin, John William Bieber, Gary Paul Zank Jun 2003

Nonlinear Collisionless Perpendicular Diffusion Of Charged Particles, William H. Matthaeus, Gang Qin, John William Bieber, Gary Paul Zank

Aerospace, Physics, and Space Science Faculty Publications

A nonlinear theory of the perpendicular diffusion of charged particles is presented, including the influence of parallel scattering and dynamical turbulence. The theory shows encouraging agreement with numerical simulations.