Three-body Halos. IV. Momentum Distributions after Fragmentation
  Momentum distributions of particles from nuclear break-up of fast three-body halos are calculated incorporating effects of final state interactions. The same two-body interactions between the particles are used to calculate both the ground state structure and the final state of the reaction processes. The ground state wave function reproduces size and energy of the halo nucleus. First we give a general and detailed description of the method. Then we investigate the effect of final state interactions in neutron removal and core break-up reactions for one- and two-dimensional momentum distributions. We compute specifically core and neutron momentum distributions from 11Li fragmentation and compare those with available experimental data. We conclude that 11Li must have a neutron-core relative state containing a p-state admixture of 20\%-30\%. The fragmentation data also strongly suggest that 10Li has an s-state at about 50 keV and a p-state around 500 keV. 
E. Garrido, D.V. Fedorov and A.S. Jensen (Institute of Physics and   Astronomy, Aarhus University, Denmark)