Superposition of Dressed Test Particles

Abstract

Kinetic theory for a spatially homogeneous plasma with Coulomb interaction is considered within the framework of the adiabatic approximation or secular perturbation theory. Time dependent solutions are obtained for the pair correlation function, multiple time distribution functions, etc. Auto correlation functions and spectral densities for fluctuating quantities are defined and obtained for a stable or unstable plasma. The results show that the plasma behaves as though it consisted of statistically independent quasiparticles. The relationship between test-particle problems and the more general kinetic theory is clarified. Physical interpretation of each term in the Fokker-Planck equation is provided in terms of spontaneous emission, induced emission, and absorption.