3-WAVE PROCESSES IN A TURBULENT NONSTATIONARY PLASMA

The contribution of plasma turbulence to the decay-type coupling of th ree regular waves is derived and discussed. The effect is due to the n onlinear interaction of the waves with the turbulence as well as the p lasma nonstationarity induced by the turbulence. The conservation rela tions for the wave occupation numbers, energy, and momenta are conside red. It is shown that for the interactions of three regular waves in a closed system, the Manley-Rowe relations are valid (i.e., there is no exchange of the number of quanta with the plasma turbulence). However , the turbulence causes phase shifts of the interacting waves, and aff ects the energy balance via the nonstationarity of the system. (C) 199 7 American Institute of Physics.