Structural ion-sound plasma turbulence as a self-similar random process

It is shown that the experimentally investigated structural ion-sound plasm a turbulence is a self-similar stationary random process. The self-similari ty parameter is determined by two temporal laws: the nonrandom character of the appearance of nonlinear structures (nonlinear ion-sound solitons) in t he plasma, and the nonlinear interaction between them. As the distance from the threshold of the ion-sound current instability increases, the self-sim ilar random process approaches a Gaussian random process, but this limit ha s not been attained experimentally. The possibility of recording superlong time series of the fluctuations of the signal of the plasma process and pro cessing of the time series by the R/S analysis method has made it possible to prove self-similarity of the plasma structural turbulence. (C) 1999 Amer ican Institute of Physics. [S0021-3640(99)00915-9].