Determination of transition probabilities for argon using Thomson scattering on an inductively coupled plasma

The inductively coupled plasma is used as an emission source for determining transition probabilities of highly excited argon states. The population densities of these higher levels are assumed to be populated according to the Saha formula. To establish the Saha line we used the electron temperature from Thomson scattering together with the densities of three well-known levels by absolute line emission intensity measurements. In order to determine the transition probabilities the corresponding absolute line emission of 15 levels is measured using a two-dimensional optical multichannel analyser and is subsequently compared to the Saha line. The obtained transition probabilities have estimated maximum errors of less than 20% whereas the original specified inaccuracies are in most cases larger than 50%. Copyright (C) 1996 Elsevier Science Ltd.