Laser-induced-vaporisation mass-spectrometry studies on UO2, UC, and ThO2

Partial pressures of different species present in the vapour phase over UO2, UC, and ThO2 have been studied at very high temperatures (> 3000 K), by transient heating of the sample with a 532 nm laser pulse of similar to 8 ns duration with time-resolved mass-spectrometric detection. The surface temperature was varied by changing the laser incident power density on the sample. In the case of the UO2 system, which has been studied extensively, these results serve for comparison; and in the case of UC they provide additional information. For the ThO2 system, this study gives the first information for very high temperatures.