Observation of the Yrast and Statistical Cascades in (Heavy-Ion,xnγ) Reactions

Abstract

The energy spectra and angular distributions of the yrast and statistical cascades in ${}_{}{}^{160,162}{}_{}{}^{}\mathrm{Yb}$ have been obtained from measurements of the reactions ${}_{}{}^{147,149}{}_{}{}^{}\mathrm{Sm}({}_{}{}^{16}{}_{}{}^{}\mathrm{O}, 3n)$ and ${}_{}{}^{148,150}{}_{}{}^{}\mathrm{Sm}({}_{}{}^{16}{}_{}{}^{}\mathrm{O}, 4n)$. An average of about six yrast and six statistical $\gamma$ rays occur in the $4n$ reaction. The data suggest that the yrast $\gamma$ rays are mostly stretched $E2\mathrm{}$.