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An experiment was performed at the Australian National University to study the 9 Be( 6 Li, 6 Li) 9 Be * → α + α + n reaction. This experiment was designed to study the breakup of 9 Be, in an attempt to quantify the contribution played by the 5 He + α and 8 Be 2 + + n channels for the low lying excited states. This information is required in order to resolve uncertainties in the α + α + n → 9 Be reaction rate in high-energy and neutron-rich astrophysical environments such as supernovae. Angular correlation measurements have been used to deduce that the 2.429 MeV state breaks up almost exclusively via the 8 Be 2 + channel. This method of identifying the break-up channel resolves the problem of distinguishing between the 8 Be 2 + and 5 He g.s. channels which are kinetically identical at this excitation energy.

An experiment was performed to study the 9 Be( 6 Li, 6 Li) 9 Be * → α + α + n reaction. This experiment was designed to study the breakup of 9 Be in an attempt to quantify the breakup yield for each of the decay channels (n + 8 Be g.s , n + 8 Be 2 + , and α + 5 He g.s ) from the low-lying states. The results suggest that the population of states in 9 Be from 1.68 to 11.28 MeV can be identified. Branching ratios for each of the breakup channels have been estimated for these states. These results are compared with earlier experiments and with theoretical predictions. They confirm the theoretical claim that the n + 8 Be 2 + and α + 5 He g.s channels increase in importance at higher excitation energies.