Nonlinear excitation of short scale turbulence in solar corona by kinetic Alfvén waves

Abstract

The model equations for the nonlinear interaction between kinetic Alfvén waves and ion acoustic waves in the intermediate-β (thermal to background magnetic pressure ratio) plasmas are presented. The nonlinear dynamical equations satisfy the modified Zakharov system of equations by taking the nonadiabatic response of the background density. Numerical solution has been obtained to study this nonlinear process. The localized magnetic filamentary structures are found in solar corona along with the density dips and humps associated with the kinetic Alfvén waves. The power spectra of magnetic field fluctuations indicate that the nonlinear interactions may be redistributing energy among higher wave numbers. The heating of the solar corona observed by Yohkoh and Solar and Heliospheric Observatory may be produced by the coupling of kinetic Alfvén waves and ion acoustic waves via filamentation process.