THE PROTON AND NEUTRON DISTRIBUTIONS IN NA ISOTOPES - THE DEVELOPMENTOF HALO AND SHELL STRUCTURE

The interaction cross sections for Na-A + C-12 reaction are calculated using Glauber model. The continuum Hartree-Bogoliubov theory has been generalized to treat the odd particle system and take the continuum i nto account. The theory reproduces the experimental result quite well. The matter distributions from the proton drip line to the neutron dri p line in Na isotopes have been systematically studied and presented. The relation between the shell effects and the halos has been examined . The tail of the matter distribution shows a strong dependence on the shell structure. The neutron N = 28 closure shell fails to appear due to the coming down of the 2p(3/2) and 2p(1/2). The development of the halo was understood as changes in the occupation in the next shell or the sub-shell close to the continuum limit. The central proton densit y is found to be decreasing near the neutron drip line, which is due t o the proton-neutron interaction. However the diffuseness of the proto n density does not change for the whole Na isotopes. (C) 1998 Elsevier Science B.V.