NUCLEAR-STRUCTURE AT THE DRIP LINES

This paper gives a brief review of some recent results on the structure of nuclei at the boundaries of the nuclear chart, that is near to or at the limit of particle stability. The extremely neutron-rich nuclei appear especially interesting. Their low neutron separation energy combined with the fact that the nuclear force is attractive and of short range leads to a spatially extended neutron wave function, the neutron "halo", which for the case of 11Li is estimated to extend to about 8 fm, well beyond the 2.5 fm radius of 9Li. New manifestations of the halo in electromagnetic processes and beta decay are discussed. Ther first example of beta-delayed deuteron emission has been observed in the isotope 6He, and is expected to occur also in the decays of other drip-line nuclei. © 1990 IOP Publishing Ltd.