Alpha condensation in light 4N nuclei

Full text: In light nuclei we can see a various kinds of cluster states. The cluster states of stable nuclei which have no excess nucleons outside of clusters are all located near or above the threshold energy of break-up into constituent clusters. This fact which is known as the threshold rule means that the inter-cluster binding is very weak in cluster states. One of the basic questions of cluster states is what kind of image can be expected on N-α break-up in self-onjugate 4N nuclei. One possible answer is the cluster state with N-α chain structure. In a lot of studies in 24C, however, the calculated second 0+ state which corresponds to the second 0+ state located by 0.39 MeV above the 3α threshold energy is found to have the structure where α-clusters interact each other dominantly in relative s-wave. The theory has concluded that the cluster state in 12C does not have the chain structure but an α gas structure. Within the microscopic framework of α-gas, we obtain the energy schemes of 12C and 16O. In other words, a microscopic α condense model shows successful explanations of the structure of light 4N nuclei