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)


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.


Energetic Particle Solar Energetic Particle Normal Diffusion Wave Particle Interaction Corotating Interaction Region 
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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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