Zeeman Effects in the Arc Spectrum of Ruthenium

Abstract

Measurements on resolved Zeeman patterns of 450 lines of normal ruthenium are reported. Five exposures to each polarized component of the light from a 4-ampere arc, operated in magnetic fields of intensity between 71,000 and 92,200 gauss, resulted in 85 plates which were measured on an automatic comparator. $J$ and $g$ values have been determined from the various patterns. When data from the various lines arising from a given term are averaged, $g$ values for 140 terms are obtained which appear to be correct to within ±0.003 unit. The results obtained have been used to further the classification of Ru I, and to aid in the assignment of $L$ and $S$ values to highly perturbed terms. Though $g$ values frequently depart strongly from values calculated for $\mathrm{LS}$ coupling, it is usually possible to assign meaningful $L$ and $S$ designations. Asymmetrical patterns in lines arising from the terms $y^{5}D_3^{}{}_{}{}^0$ and $y^{5}D_4^{}{}_{}{}^0$ are discussed.