NUCLEAR ALPHA-CLUSTERING, SUPERDEFORMATION, AND QUASIMOLECULAR RESONANCES

Nuclear alpha-clustering has been the subject of intense study since the advent of heavy-ion accelerators. Looking back for more than 40 years we are able today to see the connection between quasimolecular resonances in heavy-ion collisions and extremely deformed states in light nuclei. For example superdeformed bands have been recently discovered in light N=Z nuclei such as 36Ar, 40Ca, 48Cr, and 56Ni by γ-ray spectroscopy. The search for strongly deformed shapes in N=Z nuclei is also the domain of charged-particle spectroscopy, and a number of these nuclei have been studied with the charged particle multidetector array ICARE at the VIVITRON. Recently the search for γ-decays in 24Mg has been undertaken in a range of excitation energies where previously nuclear molecular resonances were found in 12C+12C collisions. The breakup reaction 24Mg+12C has been investigated at an energy which corresponds to a 12C+12C resonance. Very exclusive data were collected with the Binary Reaction Spectrometer in coincidence with EUROBALL IV installed at the VIVITRON. Results on the population of specific structures of large deformation will be presented.

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