  The proton and neutron density distributions, one- and two-neutron separation
energies and radii of nuclei for which neutron halos are experimentally
observed, are calculated using the self-consistent Hartree-Fock-Bogoliubov
method with the effective interaction of Gogny. Halo factors are evaluated
assuming hydrogen-like antiproton wave functions. The factors agree well with
experimental data. They are close to those obtained with Skyrme forces and with
the relativistic mean field approach.
