ULYSSES at High Solar Latitudes: The Signature of Evolving Turbulence in Quiet Fast Solar Wind

Mathematics – Probability

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2159 Plasma Waves And Turbulence, 2162 Solar Cycle Variations (7536), 2169 Solar Wind Sources, 3270 Time Series Analysis (1872, 4277, 4475), 4440 Fractals And Multifractals

Scientific paper

The Ulysses spacecraft spent many months at high heliospheric latitudes above the Sun's polar coronal holes, in the quiet fast solar wind with a highly ordered magnetic field. The power spectra of fluctuations in solar wind bulk parameters, such as the magnetic field, show inverse power law behaviour that contains both an inertial range of intermittent turbulence and, at lower frequencies, a scaling range with approximate "1/f" dependence. Here we use statistical analysis methods, such as the generalized structure function (GSF) and extended self-similarity (ESS), to quantify the scaling of the moments of the probability density function of fluctuations in the magnetic field. We present corroborating results from both the South 1994 and the North 1995 polar passes by Ulysses. GSF is sufficient to reveal approximate power law scaling for the "1/f" range, and we test the resultant scaling exponents for secular trends with heliospheric latitude and with radial distance from the sun. At higher frequencies, where we would anticipate an inertial range of turbulence, the scaling properties of the structure functions, as well as being characteristic of intermittent turbulence, also show evidence of an 'envelope' function which we identify. We find that within these regions of quiet fast polar flows, this envelope function does not vary with heliospheric radius or latitude, and in particular is the same for both polar passes. This suggests that while the higher frequency, or inertial range, fluctuations found in the solar wind at high heliospheric latitudes are consistent with locally evolving turbulence, their envelope also reflects some aspects of the evolution of coronal structure and flows into the quiet fast solar wind. RN acknowledges the STFC and UKAEA Culham for financial support and A. Balogh and the ULYSSES team for data provision.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

ULYSSES at High Solar Latitudes: The Signature of Evolving Turbulence in Quiet Fast Solar Wind does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with ULYSSES at High Solar Latitudes: The Signature of Evolving Turbulence in Quiet Fast Solar Wind, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and ULYSSES at High Solar Latitudes: The Signature of Evolving Turbulence in Quiet Fast Solar Wind will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1091774

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.