Microscopic structure of coexisting 0+ states in 68Ni probed via two-neutron transfer

The structure of low-spin states originating from shape-coexisting configurations in
68
40
Ni
28
was directly probed via the two-neutron transfer reaction
66
Ni
⁢(𝑡,𝑝)⁢
68
Ni
in inverse kinematics using a radioactive ion beam on a radioactive target. The direct feeding to the first excited 0+ state was measured for center-of-mass angles 4∘–16∘ and amounts to an integral of 4.2(16)% relative to the ground state. The observed difference in feeding of the 0+ states is explained by the transfer of neutrons, mainly in the 𝑝⁢𝑓 shell below 𝑁=40 for the ground state, and across 𝑁=40 in the 𝑔9/2 orbital for the 0+
2, based on second-order distorted-wave Born approximation calculations combined with state-of-the-art shell-model two-nucleon amplitudes. However, the direct feeding to the 2+
1 state [29(3)%] is incompatible with these calculations.

Authors: F. Flavigny, J. Elseviers, A. N. Andreyev, C. Bauer, V. Bildstein, A. Blazhev, B. A. Brown, H. De Witte, J. Diriken, V. N. Fedosseev, S. Franchoo, R. Gernhäuser, M. Huyse, S. Ilieva, S. Klupp, Th. Kröll, R. Lutter, B. A. Marsh, D. Mücher, K. Nowak, T. Otsuka, J. Pakarinen, N. Patronis, R. Raabe, F. Recchia, P. Reiter, T. Roger, S. Sambi, M. Seidlitz, M. D. Seliverstov, B. Siebeck, Y. Tsunoda, P. Van Duppen, M. Vermeulen, M. Von Schmid, D. Voulot, N. Warr, F. Wenander and K. Wimmer

Doi: https://doi.org/10.1103/PhysRevC.99.054332

Issue number:

Journal: Phys. Rev. C

Page number: 054332

Published on: 2019-05-31

Year: