Solar Physics

, Volume 285, Issue 1–2, pp 97–110 | Cite as

Equatorwards Expansion of Unperturbed, High-Latitude Fast Solar Wind

  • G. D. Dorrian
  • A. R. Breen
  • R. A. Fallows
  • M. M. Bisi
OBSERVATIONS AND MODELLING OF THE INNER HELIOSPHERE
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Abstract

We use dual-site radio observations of interplanetary scintillation (IPS) with extremely long baselines (ELB) to examine meridional flow characteristics of the ambient fast solar wind at plane-of-sky heliocentric distances of 24 – 85 solar radii (R⊙). Our results demonstrate an equatorwards deviation of 3 – 4∘ in the bulk fast solar wind flow direction over both northern and southern solar hemispheres during different times in the declining phase of Solar Cycle 23.

Keywords

Solar wind Interplanetary scintillation Fast Solar Wind Parker Spiral Radio observations Heliosphere Interplanetary magnetic field IPS 

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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • G. D. Dorrian
    • 1
    • 2
  • A. R. Breen
    • 2
  • R. A. Fallows
    • 2
    • 3
  • M. M. Bisi
    • 2
  1. 1.Institute of Astronomy and AstrophysicsNational Observatory of AthensAthensGreece
  2. 2.Institute of Mathematics and PhysicsAberystwyth UniversityAberystwythWales, UK
  3. 3.ASTRONThe Netherlands Institute for Radio AstronomyDwingelooThe Netherlands

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