ИСТИНА

Shell models of MHD turbulence describe in a simplified way the interaction of turbulent vortexes on different scales with each other [1]. Obtained by Fourier transform of plasma motion equation and magnetic induction law for a finite number of spectral shells, they make it possible to analyze the cascade of hydrodynamic and magnetic energy over the spectrum, energy accumulation and its dissipation in time. In such case, for initial weak magnetic field the plasma motion energy can be transferred into the magnetic field energy, so that the magnetic energy itself grows exponentially localized at small scales. This suggests that such a generation may be a reflection of the well-known small-scale Kazantsev dynamo process, which describes the growth of magnetic energy in loops with a typical scale comparable with the correlation length of velocity field [2]. In the present work, we verify this fact by the Kazantsev model, obtained for a turbulent plasma with short time-correlations. Using hydrodynamic spectrum obtained in cascade process, we transform it into correlation function and vary correlation time to check when models match best. Comparing the growth rates and localization regions of both models, we speculate about which part of the spectrum is responsible for the small-scale dynamo and what happens in this case with the correlation times, which play a key role in Kazantsev's approach. The work was supported by the BASIS Foundation grant no. 21-1-3-63-1.