The origin of low-energy anomalous cosmic rays at the solar-wind termination shock

Joe Giacalone, Rob Decker

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

We address the origin of the enhancement of ∼ 40keV to 5 MeV ions at the solar wind termination shock. Using self-consistent two-dimensional hybrid simulations (kinetic proton, fluid electron) of a shock moving through a plasma similar to that observed in the outer heliosphere, we conclude that the observed ion enhancements are consistent with accelerated "core" interstellar pickup ions (those that have not previously undergone any significant energization) by the termination shock via a combination of shock drift acceleration and particle scattering in meandering magnetic fields in the vicinity of the shock. In addition to the consequences for our understanding of anomalous cosmic rays, this work is also relevant to the more-general long-standing problem of accelerating low-energy particles by shocks that move nearly normal to a mean magnetic field.

Original languageEnglish (US)
Pages (from-to)91-96
Number of pages6
JournalAstrophysical Journal
Volume710
Issue number1
DOIs
StatePublished - 2010

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cosmic ray
solar wind
cosmic rays
shock
ion
magnetic field
energy
scattering
plasma
electron
kinetics
ions
fluid
augmentation
heliosphere
particle energy
magnetic fields
simulation
protons
particle

Keywords

  • Acceleration of particles
  • Cosmic rays
  • Shock waves

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

The origin of low-energy anomalous cosmic rays at the solar-wind termination shock. / Giacalone, Joe; Decker, Rob.

In: Astrophysical Journal, Vol. 710, No. 1, 2010, p. 91-96.

Research output: Contribution to journalArticle

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