Observations of Evolving Turbulence in the Polar Solar Wind
نویسندگان
چکیده
The Ulysses magnetic field experiment has measured the heliospheric magnetic field in solar wind flows from the Sun’s Southern polar coronal hole ovef a wide range of heliolatitudes and distances. We present an anatysis of more than one ym of data, covering a latitude range of 40° to 80°S and a distance range of 4.0 to 1.7 AU. We extend an earlier analysis of Utysses magnetic field data and, by calculating structure functions, demonstrate that the spectrum of fluctuations in the magnetic field changed atong the orbit of Ulysses within polar flows and that this change is a result of the variation in Ulysses’ distance from the Sun, rather than its latitude. We interpret this change as being due to the development of turbulence in the polar solar wind.
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