Measurement of atomic parameters of singly ionized argon lines—II. Transition probabilities

Abstract

In order to obsrve spectral lines of ArII, corresponding to transitions from 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 arc of Iarc = 200 A current, burning in pure argon at atmospheric pressure. Spectroscopic diagnostic of the observed zone showed, that it was characterized by high temperature and electron densities of the order of T ≈ 24,000 K and Ne ≈ 2 × 1023 m−3, respectively. Altogether, we have registered more than 90 spectral lines from different levels and configurations, e.g., for which the upper levels belong to the 4f configuration (excitation energy Ei > 24 eV), 5s and 3d″ (Ei > 22 eV). We were able to determine the transition probabilities of 92 ArII lines, relative to the 480.602 nm ArII line, and Stark widths of some 80 ArII lines. Our transition probabilities and Stark widths for ArII lines, 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 the investigated singly ionized argon lines are presented in the first part of this series. In this second part, we present our results concerning the transition probabilities of 92 singly ionized argon lines.