Progress on nuclear reactions and related nuclear structure at low energies

Abstract

Through the use of the accelerator facilities at home and abroad, the nuclear reaction group of the China Institute of Atomic Energy has made many remarkable achievements in the study of fusion-fission dynamics, fusion-enhancement mechanisms at sub-barrier energies, reaction dynamics induced by exotic nuclei, and the related exotic nuclear structure and proton decay. In this study, some representative achievements are reviewed briefly. (1) The fusion mechanisms at near-barrier energies were investigated systematically, and a self-consistent method to evaluate the coupled-channel effects was proposed. (2) Nuclear deformation parameters were extracted from backward quasi-elastic scattering, which offered evidence for hexadecapole shapes. (3) A surrogate capture method was developed, based on which the first 239Pu(n,2n) excitation function developed in China was derived. (4) Systematic studies of exotic decay spectroscopies for proton-rich nuclei in the sd-shell were performed, following which a β2p decay of 22Si and a large isospin-asymmetry decay were discovered, and a strongly isospin-mixed doublet in 26Si was revealed. (5) Systematic studies of reaction mechanisms induced by exotic nuclei at energies close to the Coulomb barrier were performed, providing evidence for the failure of the dispersion relation in the optical potential of 6He+209Bi, and the reaction dynamics of proton drip-line nuclei of 8B and 17F were investigated. Future research based on the new HiTOF and BRIF facilities is discussed as well.

Keywords

• nuclear reactions induced by heavy ions
• energies close to the coulomb barrier
• exotic nuclear structure