Reemission of neutral hydrogen molecules from tungsten

Vibrational distribution of H2 and D2 molecules emitted from tungsten surface exposed to the continuous flow of partially dissociated neutral hydrogen gas is studied. A special vibrational spectrometer is used for this study. Vibrational distributions can be well described by vibrational temperatures being TV = 3700 ± 100 K for H2 and TV = 3400 ± 100 K for D2. To gain more detailed information on the state of the tungsten surface we employed ion beam analytical method ERDA for in situ determination of H/D concentration. Both experiments indicate high importance of impurity layer (presumably oxide) on the observed phenomena.