Intruder configurations in the ground state of Ne-30

We report on the first detailed study of intruder configurations in the ground state of Ne-30 by means of the C-12(Ne-30, Ne-29+gamma) X one-neutron knockout reaction at 228MeV/nucleon. Using a combined analysis of individual parallel momentum distributions and partial cross sections we find: (a) comparable pand d-wave removal strength to Ne-29 final states with excitation energies below 200keV, and (b) significant p-wave removal strength to the 620keV state of Ne-29, and (c) no evidence for f-wave intruder strength leading to bound Ne-29 final states. The SDPF-U-MIX shell model calculation in the sd-pfmodel space provides a better overall agreement with the measured energy levels of Ne-29 and the fp-intruder amplitudes in Ne-30 than the SDPF-M prediction, suggesting that the refinement of the sd-pfcross shell interaction and extension of the model space to include the 2p(1/2) and 1f(5/2) levels are important for understanding the island of inversion. (C) 2017 The Authors. Published by Elsevier B. V. This is an open access article under the CC BY license.Science and Technology Facilities Council (UK) [ST/L005743]; MINECO (Spain) [FPA2014-57196]; Programme "Centros de Excelencia Severo Ochoa" [SEV-2012-0249]SCI(E)ARTICLE58-6276