Small-scale gradients and large-scale diffusion of charged particles in the heliospheric magnetic field

Research output: Contribution to journalArticle

97 Citations (Scopus)

Abstract

We have carried out numerical simulations of the propagation of energetic charged particles in a turbulent magnetic field similar to that observed in the solar wind. If the particles are released impulsively near the Sun, in a region small compared with the field coherence scale (a solar flare, for example), they exhibit characteristic fluctuations in intensity at 1 AU (dropouts) associated with very steep localized gradients. These numerical simulations are quantitatively very similar to recent observations by the Advanced Composition Explorer spacecraft and are the result of the convection of alternatively filled and empty flux tubes past the spacecraft. These fluctuations occur naturally as part of the particle transport in the same field, which results in large-scale cross field diffusion and which has previously been used to study the propagation of corotating interaction region-associated particles to high heliographic latitudes.

Original languageEnglish (US)
JournalAstrophysical Journal
Volume532
Issue number1 PART 2
StatePublished - Mar 20 2000

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charged particles
magnetic field
gradients
spacecraft
magnetic fields
Advanced Composition Explorer
dropouts
propagation
energetic particles
solar flares
polar regions
solar wind
sun
convection
simulation
tubes
energetics
particle
interactions

Keywords

  • Cosmic rays
  • Diffusion
  • Sun: flares
  • Sun: magnetic fields

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Small-scale gradients and large-scale diffusion of charged particles in the heliospheric magnetic field. / Giacalone, Joe; Jokipii, J. Randy; Mazur, J. E.

In: Astrophysical Journal, Vol. 532, No. 1 PART 2, 20.03.2000.

Research output: Contribution to journalArticle

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