Structure of Be 12 : Intruder d -Wave Strength at N = 8

Department of Physics, University of Surrey, Guilford, England, United Kingdom
Physical Review Letters (Impact Factor: 7.51). 02/2006; 96(3):032502. DOI: 10.1103/PhysRevLett.96.032502
Source: PubMed


The breaking of the N=8 shell-model magic number in the 12Be ground state has been determined to include significant occupancy of the intruder d-wave orbital. This is in marked contrast with all other N=8 isotones, both more and less exotic than 12Be. The occupancies of the [FORMULA: SEE TEXT]orbital and the [FORMULA: SEE TEXT], intruder orbital were deduced from a measurement of neutron removal from a high-energy 12Be beam leading to bound and unbound states in 11Be.

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