At present, studies of structural plasma turbulence attract particular attention both in fundamental aspect and in connection with the long-standing problem of anomalous heat and particle transport in magnetic confinement systems. A distinct feature of the structural low-frequency turbulence is the presence of stochastic plasma structures which comprise a considerable fraction of energy of plasma turbulent fluctuations [1]. From experimental data of scattering and probes measurements in LHD and L2-M stellarator plasma was obtained that the time samples of fluctuating plasma variables in the structural turbulence are described by stable probability density distributions that differ from normal (Gaussian) distributions by heavy tails and sharper vertexes. It is common knowledge that non-Gaussian probability densities of stochastic plasma processes indicate to non-Brownian motion (diffusion) of particles in such stochastic fields. The role of rare events, i.e., of stochastic plasma processes that occur on substantially larger space-time scales in comparison with their average values, increases. For more deep investigation of turbulent processes in plasma it is proposed to use the mathematical modeling of the increments of fluctuation plasma variables to analyzing the probability characteristics of plasma turbulent parameters[2]. It is shown, that in plasma of LHD and L2-M stellarator the increments of fluctuations are stochastic in nature and their distribution is a scale mixture of Gaussians. Next step of turbulent processes in plasma investigation is the use of mathematical apparatus of the trajectories stochastic differential equations to construction of stochastic model of process of turbulent transport in plasma. The estimation of possibility of this mathematical method using for turbulent plasma was performed.

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