Dynamic screening effects in plasma line broadening

The results of a kinetic theory of spectral-line broadening are applied to the calculation of Stark broadening for the Lyman-$\alpha$ line in the classical-path approximation. In the small-plasma-parameter limit, the width and shift operator reduces to an average binary electron-atom collision operator with screened interactions and dynamic correlations. The effects of screening, particularly the variation with frequency, are indicated for a simplified model and compared with the corresponding model without screening but with an impact-parameter cutoff in the collision integral. Comparison with the dynamically screened second-order (Born approximation) collision integral is also given.