Wolf-Christian Mueller
TU Berlin, Plasma-Astrophysics, Berlin Germany

Non-asymptotic and non-universal turbulence in magnetic fields

Magnetohydrodynamic (MHD) turbulence in a mean magnetic field can exist in fundamentally different regimes. Its character can, for example, be changed from "weak" to "strong" where these attributes basically express different ratios of characteristic timescales of the system. This possibility of manipulation can be exploited by carefully changing the large-scale excitation mechanism of the turbulence. A regime of "weakened" MHD turbulence is presented that exhibits isotropic similarity properties which are beyond the current theoretical understanding of turbulence in magnetic fields and whose dynamics are explained in terms of quasi-resonant nonlinear interactions.