The measurement of vacuum-UV line intensities for neon-like ions generated in a θ-pinch device

The relative intensities of spectral lines from Δn = 0 transitions in 2p53l configurations of neon-like Ar8+ and Cl7+ are measured in a plasma generated with a θ-pinch device. Six of these lines involving 3p-3s transitions have exhibited significant amplification in high density plasmas of higher-Z elements, but with considerable disagreement compared to numerical predictions. Agreement in the present experiment indicated that the collisional excitation, mixing, and radiative decay in the modeling is accurate, at least for the ions measured. Data supporting this on 3d-3p as well as 3d-2p and 3s-2p transitions are presented. The emphasis here is on the measurements performed. For example, an essential instrumental relative intensity calibration by a branching ratio technique is described in detail.