New emissin spectrometers for multielement analysis with pulse operated plasma source and time-gated detector

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A new MIP source driven with several hundred-watt microwave of short duration, which selectively emitts temporally-intense atomic lines, was designed and constructed for allowing the trace element analysis. The use of non-cooled cavity and no requirement of heavy duty coaxial power cable are part of its notable features. For the direct vaporization of solid materials and precise control of the atom vapor introduction to the source, a tenporally and spacially stable spark source was attached. The combination of the modulated MIP and the spark atomizer was extreamely effective to yield simple and sharp atomic line spectra with a negligibly low back ground signal, facilitating quantitave element analysis with high precision.A miltichannel detection system using a gated silicon intensified target(SIT) vidicon was constructed for dynamic spectrophotometry. The linearity and dynamic range were carefully measured and theoretically analyzed for applications such as time-resolved intensity ratio measurements of pulse operated plasma sources.A new time-gated atomic fluorescence spectrometer with RF pulsed HCL as an excitation source was developed and evaluated for trace element analysis. A peak area detection mode of photon counting operation was found effective to extend the dynamic range of the element analysis.