Plasma polarization shift: An improved quantum-mechanical treatment

Using an improved quantum mechanical treatment of the plasma polarization shift theory, calculations have been made for plasma conditions corresponding to available measurements of the shift of Heii resonance lines. Agreement with experimental results at low density is found but large discrepancies still exist at high density. Comparison with other theories leads to agreement with a corrected version of the semi-classical treatment of the effect although discrepancies of one order of magnitude are found with the only quantum treatment presently available.