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arXiv · 0904.2900

Evolution of Near-Sun Solar Wind Turbulence

P. K. Manoharan
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Abstract

This paper presents a preliminary analysis of the turbulence spectrum of the solar wind in the near-Sun region R < 50 Rs, obtained from interplanetary scintillation measurements with the Ooty Radio Telescope at 327 MHz. The results clearly show that the scintillation is dominated by density irregularities of size about 100 - 500 km. The scintillation at the small-scale side of the spectrum, although significantly less in magnitude, has a flatter spectrum than the larger-scale dominant part. Furthermore, the spectral power contained in the flatter portion rapidly increases closer to the Sun. These results on the turbulence spectrum for R < 50 Rs quantify the evidence for radial evolution of the small-scale fluctuations (</= 50 km) generated by Alfven waves.

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P. K. Manoharan. 2009-04-19. Evolution of Near-Sun Solar Wind Turbulence. https://doi.org/10.1007/978-3-642-02859-5_27

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