Multiscale solar wind structure and nonextensive 
statistical mechanics.

L. F. Burlaga

The solar wind speed and magnetic field fluctuations throughout the 
heliosphere have a complex structure on scales from 1 minute to 1 
year. Understanding this structure involves both dynamics (mechanics) 
and probability (statistics), so it is natural to study it using 
statistical mechanics. The classical Gibbs-Boltzmann statistical 
mechanics is not adequate for solar wind studies. However, the 
generalization of this theory by Tsallis to describe systems with 
scaling and multifractal properties provides a powerful new way to 
describe and analyze the multiscale structure of the solar wind 
observed by ACE at 1 AU and Voyager 1, now at 91 AU.