Measurement of atomic parameters of singly ionized argon lines .3. Stark broadening parameters

In order to observe ArII transitions between levels of high excitation energy, and to have the highest possible temperature and free electron density in the applied light source, we have observed side-on the near-cathode zone of an electric are of I-arc = 200 A current, burning in pure argon at atmospheric pressure. Spectroscopic diagnostics of the observed zone showed that it was characterized by a high temperature and an electron density of the order T approximate to 24,000 K and N-e approximate to 2 x 10(23) m(-3), respectively. Altogether, we have registered more than 90 spectral lines from different levels and configurations, for which the upper levels belong to the 4f configuration (excitation energy E(i) > 24 eV), as well as 5s and 3d'' (E(i) > 22 eV). Our data, the transition probabilities and Stark widths of some 90 and 80 ArII lines, respectively, in many cases measured for the first time, are consistent with the best data published up to now and give one of the most complete sets of results. The applied experimental procedure and characteristics of investigated singly ionized argon levels are presented in the first part of this paper. In this third part, we present the results of our measurements of the Stark widths for 80 ArII lines. (C) 1997 Elsevier Science Ltd.