Emission ofHe4reflects different facets of excited nuclei

Statistical model calculations have been made for ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ emission from various excited nuclei. The energy and angular momentum removal has been calculated for each point in the $E-J$ plane. By careful choice of the excited nucleus it is possible to select each type of ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ emission, essentially pure. Several characteristics are reported for ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ emission from yrast traps.