Microscopic four-cluster description of 10Be and 10C with the stochastic variational method

Abstract

The structure of the 10 Be nucleus has been studied by using fully antisymmetrized 10-nucleon wave functions built in a microscopic α+α+n+n four-cluster model. The effective two-nucleon interaction employed contains central and spin–orbit components as well as the Coulomb potential. Stochastic optimization of basis functions has been applied to obtain not only the ground-state but also other bound excited-states which lie below the 9 Be+n threshold. Calculated energy spectra and electromagnetic transition rates are in reasonable agreement with experiment. The calculation has reasonably well reproduced the second 0 + state at 6.18 MeV as well as the tightly bound ground-state. The second 0 + state has been found to have spatially very extended structure in which two α-particles are separated like in 8 Be. The change of neutron and proton density distributions is analyzed for 8 Be to 10 Be as a function of the number of valence neutrons outside two α-particles. The basis functions obtained for 10 Be are used to calculate some of the properties of its mirror nucleus 10 C.