| Popis: |
Coupled kinetic equations for the density of plasmas Nkα(t) and spatially averaged distribution function fj(v, t) are presented in the electrostatic approximation for a weakly turbulent, unmagnetized plasma. Discrete particle collisions are neglected, and resonant three‐wave processes (ωkα = ωk′β+ωk″γ, k = k′+k″) are assumed to provide the dominant collective interaction mechanism. By taking appropriate velocity moments of the kinetic equations for the particles, rate equations for the changes in (spatially averaged) mean velocity Vj(t) and kinetic energy relative to the mean Kj(t) for each plasma component are derived. The resulting rate equations describe the bulk features of the reaction of the particle distributions (i.e., acceleration and heating rates) to resonant three‐wave interactions, and are applicable in both the nonlinearly stable and explosively unstable regimes. As an example corresponding to explosive instability, the self‐consistent evolution of well‐displaced counterstreaming ion beams i... |
