Cluster structure in low mass boron and carbon nuclides

• Main Author: Harlin, Christopher William
• Published: University of Surrey 2008
• Subjects: 539.74
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493031

Molecular states in 8B, 10B, 11B, 11C and 12C, have been studied in the reactions 6Li+12C at 60MeV 10B+ 12C and at 84.5 MeV. Final states in these nuclides were kinematically recon structed from the measured energies and angles of the charged decay products. The original motivation was to identify theoretically predicted, but so far unobserved, three-centre molecular states in 8B. No evidence for these was found. However, the 7Be+p decay of low energy 8B states was observed. The decays of the nuclides with mass 10, 11 and 12 via d and ? emission allowed the study of two-centre and three-centre structures in these systems. The results are generally more complete and the spectra of higher quality than previous work. The data for triple-alpha break-up of 12C are assessed in terms of a recently re-introduced method of spin assignment based upon Dalitz plots. New high excitation energy states that selectively decay to 8Be(gs)+4He have been observed. States in 10B, including a new high excitation level, are reviewed in light of the results of the present work. The results are related to previous studies and discussed with reference to rotational structures, particularly in the mirror pair 11B and 11C. In those A = 11 nuclides T = 3/2 states are observed in the T = ½ alpha-decay channel.