Pairing-induced localization of the particle continuum in weakly bound nuclei

The Hartree-Fock-Bogolyubov (HFB) problem for the cutoff local energy-densi ty functional is served numerically by using the Gor'kov formalism with an exact treatment of the particle continuum. The contributions from the reson ant and "gas" continuum to the spectral density of the HFB eigenstates as w ell as the shifting and broadening of the discrete HF hole Ca-70. The struc ture of the neutron orbitals are clearly demonstrated with the illustrative example of the drip-line nucleus density distribution in the localized gro und state is analyzed, and the formation of its extended tail ("halo") is s hown to be a collective pairing effect. (C) 2000 Published by Elsevier Scie nce B.V.