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Solar Physics

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

Equatorwards Expansion of Unperturbed, High-Latitude Fast Solar Wind

  • G. D. DorrianEmail author
  • 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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Notes

Acknowledgements

We would like to thank the directors and staff of both the European Incoherent SCATter (EISCAT) radar consortium and the Multi-Element Radio Linked Interferometer Network (MERLIN). EISCAT is supported by the scientific research councils of Finland, France, Germany, Japan, Norway, Sweden, the UK, and China. MERLIN is supported by the UK Science and Technology Facilities Council (STFC). Four of us (Dorrian, Breen, Fallows, and Bisi) were also supported by STFC throughout the majority of this research.

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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • G. D. Dorrian
    • 1
    • 2
    Email author
  • 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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