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Observations of Electromagnetic Fluctuations at Ion Kinetic Scales in the Solar Wind

  • John J. Podesta
Conference paper
Part of the Astrophysics and Space Science Proceedings book series (ASSSP, volume 33)

Abstract

Wavelet techniques enable reduced power spectra and cross-spectra to be analyzed as a function of the angle θ BV formed by the scale dependent local mean magnetic field B 0 and the flow direction of the solar wind. These techniques allow the data along a line oriented at any angle θ BV to B 0 to be isolated and studied independently thus providing new information about the properties of the fluctuations along directions parallel, perpendicular, and at arbitrary angles to the local mean magnetic field. Recent investigations of the normalized magnetic helicity spectrum σ m using this technique have revealed the existence of two distinct populations of fluctuations near the proton inertial length scale, that is, at wavenumbers near \(kc/{\omega }_{pp} = 1\). These observations and their physical interpretation are briefly reviewed.

Keywords

Solar Wind Spectral Break Inertial Range Solar Wind Flow Solar Wind Turbulence 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

I am grateful to Manfred Leubner and Zoltán Vörös for the invitation to the International Astrophysics Forum Alpbach 2011 held in Alpbach, Tyrol, Austria in June 2011. And to S. Peter Gary for helpful discussions and comments on the manuscript. This research was supported by NASA’s Solar and Heliophysics Program and the NSF Shine program.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Los Alamos National LaboratoryLos AlamosUSA

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