Alternative evaluations of halos in nuclei

Data for the scattering of {sup 6}He, {sup 8}He, {sup 9}Li, and {sup 11}Li from hydrogen are analyzed within a fully microscopic folding model of proton-nucleus scattering. Current data suggest that of these only {sup 11}Li has a noticeable halo. For {sup 6}He, we have also analyzed the complementary reaction {sup 6}Li({gamma},{pi}{sup +}){sup 6}He{sub g.s.}. The available data for that reaction support the hypothesis that {sup 6}He may not be a halo nucleus. However, those data are scarce and there is clearly a need for more to elicit the microscopic structure of {sup 6}He. (c) 2000 The American Physical Society.