Large collectivity in Ne-29 at the boundary of the island of inversion

The heavy-ion inelastic scattering of the neutron-rich nucleus 29Ne to its excited states was studied using a 100.1 MeV/u 29Ne rare isotope beam on 181Ta and 9Be targets. The combined setup consisting of the GRETINA array, the TRIPLEX device and the S800 Spectrograph facilitates the simultaneous measurements of the two inelastic reactions, providing the first measurement of the transition strengths for this isotope. A sizable E2 strength B(E2 up arrow) which amounts to 163(30) e2 fm4 was determined in the excitation to the 931-keV state, demonstrating a large degree of collectivity. The present results of B(E2 up arrow) are compared to various shell-model calculations, confirming the role of intruder configurations in 29Ne at the boundary of the island of inversion.(c) 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3.