Cluster structure in nuclei

Abstract

Two topics of the cluster structure study are discussed. They are (1) α cluster condened states, and (2) superdeformation and molecular states in³²S In the first topic, I show that the 3α microscopic cluster model wave functions which were obtained long time ago for the¹²C second 0+ state are almost completely the same as single 3α condensate model wave functions. The α condensate model wave functions we used for this study are obtained by projecting out good angular momenta from intrinsic a condensate wave functions which are spatially deformed. It is found that the effect of deformation is not large for the present case of the¹²C O₂⁺ states in the sense that the obtained wave functions contain the spherical condensate components more than 90 %. In the second topic, I show from the AMD + GCM study that the superdeformed excited rotational band in³²S is the same as the¹⁶O +¹⁶O lowest molecular band. I explain that the AMD + GCM calculation gives not only the¹⁶O +¹⁶O lowest molecular band which is identified as the superdeformed excited band but also the¹⁶O +¹⁶O second and third lowest molecular bands whose excitation energies are higher than the lowest band by about 10 MeV and 20 MeV, respectively. I point out that the excitation energies of these three lowest bands are almost the same as those of the three lowest bands generated by the so-called “unique optical potential” of the¹⁶O +¹⁶O scattering.