NONLINEAR ELECTRONIC WAVES IN WARM PLASMAS

The properties of nonlinear longitudinal electronic waves propagating through warm plasma are examined. Thus, using the kinetic theory and t he reductive perturbation method in the third order of approximation, it is shown that the nonlinear wave-wave interactions lead to phase ve locity shifts. When the thermal velocity, nu(T), is much smaller than the phase velocity, nu(f) (nu(T)much less than nu(f)), an energy trans fer appears from the wave to the plasma electrons, together with a dec rease in the phase velocity. However, when electrons with high velocit ies V(z)much greater than nu(f) are injected in plasma, they determine an energy transfer from the particles to the wave and an increase in the phase velocity, too. (C) 1998 American Institute of Physics. [S107 0-664X(98)02612-3].