The measurement of energy parameters for atoms sputtered in excited states

Ti I lines from excited Ti atoms sputtered from Ti and a variety of Ti compounds by 55 keV Ar⁺ bombardment have been studied and the intensity decay, as a function of distance, has been measured in front of the target surface for normal incidence bombardment. These decay curves have been analyzed using the model of Dzioba et al. The model has been examined with respect to its internal consistency in the predictions for integral and differential yield measurements using several Ti I and an Al I line. Although care must be taken in defining an adequate slit size for each particular decay curve, the integral and differential measurements infer consistent E1 values. These values have been generally found to increase with the excitation energy of the Ti I level studied, and to decrease with surface (or bulk) contamination of O, N, C and B. Selected characteristics of photon emission are discussed in relation to the E1 values obtained.