  We use the three-body model and the sudden approximation to compute angular
correlations in high-energy fragmentation reactions of two-neutron halos on
light targets. The contribution from one-neutron absorption by far dominates
over that of neutron scattering. We use 6He (n+n+alpha) and 11Li (n+n+9Li) as
examples and study the dependence of the predictions of this model on different
physical assumptions and parameters.
  PACS number(s): 25.60.-t, 25.60.Gc, 21.45.+v}
