Measurements of line profiles of the hydrogen Hα transition from a well diagnosed gas-liner pinch are reported. The discharge is diagnosed using Thomson scattering and simultaneous spectroscopic measurements are performed giving the plasma parameters 0.5×1018 cm-3⩽ne⩽2.5×1018 cm-3 and 6 eV⩽kBTe⩽10.5 eV. The Stark width and shift are determined and compared to a selected set of experimental and theoretical data. The difference between the present results and former data, which were measured with the same device, is critically discussed.

Measurements of Stark profiles of the He II P α line at λ = 468.6 nm and of the He II P β line at λ = 320.3 nm from a well diagnosed plasma of a gas-liner pinch discharge are reported. The plasma parameters were determined independently by Thomson scattering, and we found n e = 0.5-4 × 10 18 cm −3 , k B T e = 4-7.5 eV when measurements of the He II P α line were carried out and n e = 0.4-0.9 × 10 18 cm −3 , k B T e = 3-5.4 eV for the He II P β measurements. We compare widths and shifts of the spectral lines with theoretical approximations and present new empirical scalings. While the width of the He II P α line shows significant discrepancies with lineshape theories, in the case of the He II P β line profile we find good agreement with some calculations. In particular, to investigate ion dynamic effects we present an accurate measurement of the dip in the centre of the spectral line.

We report on Stark width measurements of 2s3s-2s3 p singlet and triplet transitions along the berylliumlike sequence performed in a gas-liner pinch discharge. Simultaneously with the spectroscopic measurements we have diagnosed the plasma with Thomson scattering testing theoretical scalings of the Stark broadening with density, temperature, and spectroscopic charge number Z. The comparison of measured Stark widths with semiclassical calculations shows that the calculated temperature scaling is consistent with the experiment. However, a systematic discrepancy of measured Stark widths from theoretically predicted Z Ϫ2 scaling is found with increasing spectroscopic charge number Z. ͓S1063-651X͑98͒11605-7͔

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