Microwave plasma torch for analytical spectrometry

A microwave argon plasma torch is used to excite the spectra of various materials admixed to the working gas. It is shown that this torch is a very efficient tool for detecting extremely low impurity concentrations in the sample material. An important advantage of the method is the simplicity of testing liquid and dusty samples. The torch design and the device for spectral analysis created at the Institute of General Physics are described. The parameters of the torch plasma are estimated. These estimates agree satisfactorily with the observations of other authors. The spectroscopic studies of impurities in distilled water with the use of a plasma torch showed that the sensitivity of this technique is no worse than 10−9, which is comparable with the sensitivity of inductively coupled plasma devices.