Neutron-transfer induced breakup of the Borromean nucleus 9Be

We address the problem of evaluating neutron-transfer induced breakup cross sections caused by the Borromean nucleus ⁹Be, using the reaction ¹⁹⁷Au(⁹Be,⁸Be)¹⁹⁸Au as a test case. This reaction was recently measured over a wide range of incident energies around the Coulomb barrier. To deal with the high density of ¹⁹⁸Au states that can be potentially populated in this reaction, we employ the Ichimura, Austern, Vicent model, in which the spectrum of physical states for this system is replaced by the solutions of a complex n+¹⁹⁷Au potential, accounting effectively for the fragmentation of single-particle states into physical states. Furthermore, to account for the unbound nature of the emitted ⁸Be system, we employ a three-body model of ⁹Be. The calculated stripping cross sections are found to be in good agreement with existing data over a wide range of incident energies. The importance of taking into account the energy spread of the single-particle strength of the outgoing ⁸Be and the target-like residual nucleus is discussed.