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In this paper we briefly review the theory of plasma induced line shifts and present some experimental evidence. We then consider the effects that these shifts have on the merging of line series. Influence on continuum lowering is also discussed.

Plasma-induced line shifts to the red have been observed in a number of laser-produced plasmas. After briefly reviewing some of the more recent of these observations and a method of calculating their magnitude, two implications of the existence of these shifts are explored. Firstly, calculations show for plasma conditions such as those in the reviewed experiments the redshifts are larger for lines originating from manifolds with higher principle quantum numbers. This leads to line merging at lower densities than would be expected without considering shifts. Secondly, even though the observed shifts are small with respect to kTe they can have a substantial effect on population kinetics calculations for loosely bound states which approximate the effects of continuum lowering on level populations through the use of effective statistical weights.