Profile measurements of pressure broadened He II-lines
Helium plasmas having temperatures of 15–23 eV and electron densities of 0.8–1.6×1017 cm−3 were reproducibly established in a 10 kJoule thetapinch experiment. Radial and axial homogeneity of the plasma parameters in the discharge column could be achieved very satisfactorily by superimposing an axial magnetic bias field antiparallel in direction to the main thetapinch field. This plasma was well suited for Stark profile measurements on the He II-lines (4,686, 3,203, 2,733, 2,511 Å) in the visible and near ultraviolet and on the He II-lines (1,215, 1,085, 1,025, 992 Å) in the vacuum-UV-region. The line profiles recorded are given in the usualS(α)-representation and their halfwidth-density dependence is tabulated. Comparison is made with line shapes from other authors where available.