Photoneutron cross sections were measured for ${}^9\mathrm{Be}$ in the energy range from 1.78 to 6.11 MeV with laser-induced Compton backscattered $\gamma$ rays. Resonance parameters $[E_R,B(E1\mathrm{}),{\Gamma }_n]$ for the ${1/2}^{+}$ and ${5/2}^{+}$ states were deduced from the least-squares fit to the data, while ${\Gamma }_{\gamma }$ for the ${5/2}^{-}$ state was deduced from the energy-integrated cross section. The reaction rate $〈\alpha \alpha n〉$ is discussed.

• Received 27 April 2000

DOI:https://doi.org/10.1103/PhysRevC.63.018801