Statistical Properties of Dissipative MHD Accelerators

  • Kaspar Arzner
  • Loukas Vlahos
  • Bernard Knaepen
  • Nicolas Denewet
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3732)

Abstract

We use exact orbit integration to investigate particle acceleration in a Gauss field proxy of magnetohydrodynamic (MHD) turbulence. Regions where the electric current exceeds a critical threshold are declared to be ‘dissipative’ and endowed with super-Dreicer electric field EΩ = ηj. In this environment, test particles (electrons) are traced and their acceleration to relativistic energies is studied. As a main result we find that acceleration mostly takes place within the dissipation regions, and that the momentum increments have heavy (non-Gaussian) tails, while the waiting times between the dissipation regions are approximately exponentially distributed with intensity proportional to the particle velocity. No correlation between the momentum increment and the momentum itself is found. Our numerical results suggest an acceleration scenario with ballistic transport between independent ‘black box’ accelerators.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Kaspar Arzner
    • 1
  • Loukas Vlahos
    • 2
  • Bernard Knaepen
    • 3
  • Nicolas Denewet
    • 3
  1. 1.Paul Scherrer InstitutLaboratory for AstrophysicsVilligen PSISwitzerland
  2. 2.Institute of Astronomy, Dept. of PhysicsAristotle UniversityThessalonikiGreece
  3. 3.Mathematical Physics DeptUniversité Libre de BruxellesBruxellesBelgium

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