Evaporation of charged particles from highly deformed nucleus

Energy spectra of charged particles evaporated from compound nucleus have been of interest because current statistical-model codes do not reproduce the experimental results well. Deformation has been proposed as a cause of the observed anomaly, but an adequate theoretical expression for the emission rate from deformed nucleus is as yet lacking. We present here a closed form expression for the emission width of charged particles from nuclei of arbitrary shape. In addition, we propose a new evaporation mechanism in which charged particles are emitted while leaving the residual nucleus in its fission-saddle-point configuration. Applying this model to alpha-particle emission, we obtain a very low energy alpha-particle component which may have been observed experimentally. (orig.)