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Superdiffusive Transport at Shocks in Space Plasmas

  • Gaetano Zimbardo
  • Silvia Perri
Conference paper
Part of the Astrophysics and Space Science Proceedings book series (ASSSP, volume 33)

Abstract

Superdiffusion is characterized by a nonlinear growth of the mean square deviation with time. Superdiffusive transport can be interpreted in terms of a Lévy random walk, a stochastic process where a power-law distribution of free path lengths is allowed. Considering particles accelerated at interplanetary shocks, it is found that their intensity profile is a power-law in time in the case of superdiffusion, while it is an exponential decay for normal diffusion. Analysis of energetic particle fluxes from the Ulysses spacecraft at about 5 AU and from the Voyager 2 spacecraft at the solar wind termination shock shows that superdiffusive transport is found.

Keywords

Energetic Particle Solar Energetic Particle Normal Diffusion Wave Particle Interaction Corotating Interaction Region 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Università della CalabriaArcavacata di RendeItaly

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