Estimation of Absolute Number Densities from Shapes of Atomic Fluorescence Curves of Growth

摘要

A general purpose computer program has been developed to calculate atomic fluorescence curves of growth (COG) for a wide variety of cases and particularly for the experimentally interesting cases where the excitation source spectral bandwidth is not much different from the absorption linewidth in typical flames and plasmas. Calculations over a wide range of the variables which affect the shape of the COG in the high-number-density region show that the point of departure from linearity can be used to predict the absolute number density in the atomizer cell. For resonance atomic fluorescence, the point at which the experimental curve of growth is twofold below the low-density linear asymptote invariably occurs at koL (peak absorption coefficience x absorption pathlength) product of 2 + or -.