  In this paper, we analyze the probability density function (PDF) of solar
wind velocity and proton density, based on generalized thermostatistics (GT)
approach, comparing theoretical results with observational data. The time
series analyzed were obtained from the SOHO satellite mission where
measurements were sampled every hour. We present in the investigations data for
two years of different solar activity: (a) moderate activity (MA) period (1997)
and (b) high activity (HA) period (2000). For the MA period, the results show
good agreement between experimental data and GT model. For the HA period, the
agreement between experimental and theoretical PDFs was fairly good, but some
distortions were observed, probably due to intermittent characteristics of
turbulent processes. As a complementary analysis, the Global Wavelet Spectrum
(GWS) was obtained allowing the characterization of the predominant temporal
variability scales for both the periods and the stochastics aspects of the
nonlinear solar wind variability are discussed.
