The ground-state cross sections and angular distributions of ${}^9\mathrm{Be}(\gamma ,p),{}^9\mathrm{Be}(\gamma ,t),{}^9\mathrm{Be}\left(\gamma {,}^3\mathrm{He}\right),$ and ${}^9\mathrm{Be}(\gamma ,d)$ are reported, together with the cross section for the ${}^9\mathrm{Be}(\gamma ,d)$ reaction to the first excited state. Qualitative discussions of these cross sections are made on the basis of a simple model which assumes free clusters in ${}^9\mathrm{Be}.$ This is similar to the two-cluster model used for ${}^6\mathrm{Li}$ and ${}^7\mathrm{Li}$ for which theoretical calculations have been made. Predictions on the basis of this model indicate the importance of clustering in the photodisintegration of ${}^9\mathrm{Be},{}^6\mathrm{Li},$ and ${}^7\mathrm{Li}.$ The observed angular distributions are consistent with contributions due to $E1\mathrm{}$ and $E2\mathrm{}$ transitions.

• Received 1 December 1997

DOI:https://doi.org/10.1103/PhysRevC.59.239