Time resolved fluorescence as a direct experimental approach to the study of excitation and ionization processes in different atom reservoirsFunded under: JRC-EXPLORES 2C
Several examples of laser-excited time-resolved fluorescence waveforms are discussed to show how the essential parameters describing the interaction between the radiation and the atomic system can be directly evaluated. The results reported were obtained experimentally with relatively fast detection electronics in different atom reservoirs operated at atmospheric pressure. It is shown that the study of the complete temporal evolution of the population density of selected atomic levels, directly pumped by the laser or collisionally coupled to the laser-excited level, can provide important information about the dynamics of the interaction and the saturation behaviour of the transition as a function of the different atomisation environments. In simple cases, collisional mixing and ionisation rate coefficients can also be evaluated. The measurements discussed were obtained with the following elements: Au, Hg, Mg, Na, Pb, Sr and Tl. It is shown that the analytical relevance of the information gained from the waveforms is particularly significant when two or more lasers are used in the techniques of laser induced fluorescence (LIF) and laser enhanced ionisation (LEI) in flames and electrothermal atomisers.
Bibliographic Reference: Article: Spectrochimica Acta B (1995) 17 pp.
Record Number: 199510782 / Last updated on: 1995-07-12
Original language: en
Available languages: en