Neutron-neutron correlation approach for ¹¹Li halo structure investigation

The preemission of neutrons from ¹¹Li halo nuclei is considered. The present problems of investigation of ¹¹Li halo nucleus structure by means of the C _nn correlation function are briefly presented. The influence of the target screening on the halo neutron preemission is described. It is shown that, owing to the diminishing of the screening effect, the yield of preemission neutron pairs is expected to be much larger in the case of ¹²C than in the case of Si target. It is shown that a new experiment on a ¹²C target will allow one to solve the standing problems of C _nn and to test experimentally a recent new theory of C _nn.