Variational solution of a model breakup process

A two-dimensional model of three-body breakup with short range forces is described. The variational principle of Bryce and Mandl (1972) is applied to this model and reduced to a set of linear equations. Nonlinear parameters are determined by minimizing the deviation from unitarity. As the number of parameters in the trial wavefunction increases, the scattering amplitudes are shown to converge. For a complete solution of the problem the variational calculation is supplemented by the Born approximation. It is concluded that more complicated variational calculations are feasible.