One-dimensional Langmuir turbulence: proposal for a closure

Theoretical investigations of Langmuir turbulence are generally restricted to spatially homogeneous and isotropic conditions. Physically, however, a realistic and realizable initial condition consists of Langmuir waves released in a finite region of space. The ion component may -at least to some approximation - be assumed as initially unperturbed. Perturbations of the bulk plasma density develop subsequently as the waves dig their own cavity by the ambipolar electric fields induced by the ponderomotive forces. The aim of this work is to formulate a framework for an analysis and propose a statistical closure which leaves room for some physical understanding and intuition in the interpretation of the general problem. (author)