A discussion of the absolute f-value of atomic transitionsis given and the resulting relation between the equivalentwidth of an absorption line and the density is derived.This relation, referred to as the curve of growth, is examinedin detail over a large range of the density factor;that is, for values beyond the linear region. Accurate computationsare made for various values of the ratio of naturalto Doppler broadening and tables presented in the appendices.
An optical quartz cell was designed with a variableoptical path length. This cell was used in conjunction withan electric furnace to construct the curve of growth entirelyfrom the experimental data. The curves of growth were thencorrelated to the latest vapor pressure data yielding f-valuesfor nineteen resonance lines of ten elements.
The lines studied and the resulting f-values were Cu,λ3247 (0.322) and λ3274 (0.153); Ag, λ3281 (0.451) and λ3381(0.175); Au, λ2676 (0.76); Zn, λ3076 (0.992 x 10^(-4)); Cd, λ3261(2.05 x 10^(-3)); Ga, λ4033 (0.095); In, λ3039 (0.339) and λ4101 (0.172); Tl, λ2767 (0.219) and λ3775 (0.108); Sn, λ2863(0.332), λ3009 (0.042), and λ3175 (0.065); and Pb, λ2833(0.229), λ3639 (0.106), λ3683 (0.243), and λ4.057 (0.419).
These results are correlated to those of other investigatorsand comments made on the connection between the f-valueand the energy of the transition. For those elements whichhave a well-known f-value, the vapor pressure data are discussed.Corrections to the solar abundances are made on thebasis of the results obtained.
