An instantaneous determination for the velocity distribution of metallic atoms sputtered by the plasma-surface interaction in high-temperature plasma devices has been studied by the use of the laser fluorescence spectroscopy. A flashlamppumped long-pulse dye laser is developed for this purpose, whose frequency is linearly scanned by a PZT-tuned etalon inside the cavity. The Doppler profiles of their resonance lines can be determined during a single laser shot. Doppler profiles of sodium atoms in a vapor cell and iron atoms sputtered by ion-beam bombardment, were successfully measured by this technique. The distortion error caused by the line saturation is analytically calculated for two and three level systems. Some problems of the measurement in large plasma devices are discussed, and a preliminary experiment on the dye laser with the high repetition rate is briefly described.
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