Quadrupole collectivity of Ne-28 and the boundary of the island of inversion

摘要

The 0(g.s.)(+) -> 2(1)(+) excitation of the neutron-rich nucleus Ne-28 has been investigated via heavy-ion inelastic scattering in reversed kinematics. The B(E2; 0(g.s)(+). -> 2(1)(+)) value was determined to be 132(23) e(2) fm(4), which is smaller than expected from the low excitation energy of the first 2(l)(+) state. A comparison with theoretical predictions suggests that the suppressed collectivity in Ne-28 is characteristic of nuclei lying on the boundary of the 'island of inversion'. (c) 2005 Elsevier B.V. All rights reserved.