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Modeling a Few-MeV Jovian and Galactic Electron Spectra in the Inner Heliosphere
Ferreira, S. E. S.; Potgieter, M. S.; Henize, Vance K.
A three-dimensional numerical modulation model, based on the transport equation, is used to model the transport of a few-MeV electrons in the inner heliosphere. In particular the modulation of jovian and galactic electrons is studied with emphasis on explaining the 3-10 MeV Ulysses/KET observations after mid1998. Analysis of SOHO/CST 4 MeV electro…
Energetic Particle Observations by the Cassini Spacecraft during Its Heliospheric Cruise to Saturn
Livi, S.; Dougherty, M. K.; Lario, D. +3 more
We present energetic particle observations performed by the Cassini spacecraft during its heliospheric cruise to Saturn. We cover three years of data (20002002) during the maximum of the solar cycle 23. Cassini's helio centric radial distance ranged from 2.5 to 8.0 AU. Energetic particle intensity enhancements at these distances are associated wit…
Cosmic Ray Drifts at Solar Maximum
Ferreira, S. E. S.; Potgieter, M. S.; Heber, B.
A fully time-dep endent cosmic ray modulation model, based on the numerical solution of Parker's transport equation, is used to study the amount of particle drifts needed to explain the observed 2.5 GV electron to proton ratio (e/p) by the KET instrument on the Ulysses spacecraft. It is shown that the model successfully simulates the modulation of…
Conditional Statistics of Magnetic Turbulence and the Lateral Transport of Solar Energetic Particles
Matthaeus, W. H.; Ruffolo, D.; Chuychai, Piyanate
The transport of energetic particles perpendicular to the mean magnetic field in space plasmas long has been viewed as a diffusive process. However, there is an apparent conflict between recent observations of solar energetic particles (SEP): 1) SEP from impulsive solar flares can exhibit "drop outs" in which the intensity near Earth repeatedly di…
Perpendicular Diffusion and Drift of Solar Energetic Particles in Heliospheric Magnetic Fields
McKibben, R. B.; Zhang, Ming; Jokipii, J. R.
We present evidence for large perpendicular diffusive flows of solar energetic particles. Using anisotropy measurements of 40-90 MeV protons from the July 14th, 2000 event obtained by HET on Ulysses, we find periods of first order anisotropy directed at significant angles to the local magnetic field, which can only be satisfactorily explained by p…