A CONVERGENT THEORY OF STARK-BROADENING OF HYDROGEN LINES IN DENSE-PLASMAS

A generalized semi-classical theory of Stark broadening is developed that is free from a shortcoming of the standard semi-classical theories of Stark broadening which were intrinsically divergent at small impact parameters. A convergency of the present theory is achieved by taking into account on equal footing both a ''dynamic'' splitting of Stark sublevels caused by one of the components of the electron microfield and a quasistatic splitting of Stark sublevels caused by ion microfield (only the latter was allowed for in the standard theories). The presented generalized theory is developed analytically to the same level as the standard theories: it substitutes the ''broadening'' function C(ST)(Z) of the standard theories by a generalized but still elementary function C(Z). The generalized theory embraces the standard theories as one of its limiting cases corresponding to relatively low densities of a plasma. However for dense plasmas the predictions differ: our results demonstrate that the standard theories overestimate an electron impact broadening for high density plasmas.