On nonlinear evolution of Alfv́nic turbulence in low beta plasmas

Nonlinear evolution of broadband spectrum Alfv́nic turbulence is studied by using one-dimensional hybrid simulations. Numerical solutions indicate that the important characteristics in the solar wind magnetohydrodynamic (MHD) turbulence are naturally reproduced by nonlinear evolution of Alfv́nic turbulence with more realistic power spectrum than one used in the past studies. Namely, (i) the modulational instability can dissipate the magnetic energy of Alfv́nic turbulence and preserve the Alfv́nicity even in low beta plasmas. (ii) Nonlinear evolution of the Alfv́nic turbulence can induce the generation of the localized structures in the solar wind MHD turbulence.