Abstract
We have measured the distribution of momenta of atoms evaporating from large sodium clusters produced in a supersonic expansion source. The distributions are well described by phase space theory when polarization effects are included in the atomic capture cross section. Alternatively, the data can be fitted by a simple powerlaw preexponential. The cluster temperature extracted from both models differ, but still agree reasonable well with evaporative ensemble predictions. The data rule out a non-trivial transition state.
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References
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