Line shape modeling in warm and dense hydrogen plasmas

Abstract

A study of hydrogen lines emitted in warm ( T e ∼ 1 eV ) and dense ( N e ≥ 10 18 cm −3 ) plasmas is presented. Under such plasma conditions, the electronic and the ionic contributions to the line width are comparable, and the general question related to a transition from impact to quasi-static broadening arises not only for the far wings but also for the core of spectral lines. The transition from impact to quasi-static broadening for electrons is analyzed by means of Frequency Fluctuation Model (FFM). In parallel, direct integration of the semi-classical evolution equation is performed using electron electric fields calculated by Molecular Dynamics (MD) simulations that permit one to correctly describe the emitter environment. New cross comparisons between benchmark MD simulations and FFM are carried out for electron broadening of the Balmer series lines, and, especially, for the H α line, for which a few experiments in the warm and dense plasma regimes are available.