A theoretical study of the plasma broadening of helium-like transitions for high-Z emitters

Calculations of the spectral line broadening for 1s2 1S-1snp 1p transitions in helium-like ions have been performed for emitters with relatively high Z (silicon and argon). These calculations illustrate the plasma dependent shifts and asymmetries which are due to the high emitter charge. A discussion of the effects is presented, with particular reference to the deviations from the corresponding hydrogenic line profiles.