Convectively unstable two‐plasmon decay modes in a weakly inhomogeneous plasma

The behavior of the convective two‐plasmon decay instability is studied using a kinetic theory formulation which is applicable to high‐temperature plasmas. Theoretical values for the Langmuir wave amplification are obtained in several limits. The temperature‐dependent effects of Landau damping and kinetic theory corrections to the coupling coefficients are studied. Landau damping significantly reduces the spectrum of unstable modes for T>1 keV, while kinetic corrections become important for T>10 keV. The nonresonant scattering of Langmuir waves by thermal electrons is calculated and is found to be comparable to the resonant convective process for T>20 keV.