A hollow cathode discharge (HCD) system for atomic emission spectroscopy has been studied. This laboratory-constructed system consists of a water-cooled discharge tube connected to a PGS-2 plane grating spectrograph and radioactivity measuring apparatus, the latter including a NaI (T1) scintillator detector and a Gamma-350 spectrometer. During the simultaneous ablation-excitation of elements with different volatility, e.g. Cr-Cd, Cr-Cs, Ce-Cs, it was observed in both the spectrographic measurements and the experiments with radioactive tracers that the more volatile element in the sample is not only sputtered but also evaporated. The reason is that the melting or sublimation points of Cs and Cd are close to the temperature of the cathode wall. The simultaneous excitation of the elements in the experiments affected neither the ablation rate nor the intensity of the spectral lines, these values being equal to those obtained by ablation-excitation of the elements separately. Other phenomena taking place during the simultaneous excitation of elements (e.g., the dependence of the observed characteristics upon element concentration and ionisation potential) require further studies.
