Study of the deformation-driving d 5/2 orbital in 67Ni using one-neutron transfer reactions

The
𝜈
g
9
/
2
,
d
5
/
2
,
s
1
/
2
orbitals are assumed to be responsible for the swift onset of collectivity observed in the region below 68Ni. Especially the single-particle energies and strengths of these orbitals are of importance. We studied such properties in the nearby 67Ni nucleus, by performing a
(
𝑑
,
𝑝
)
-experiment in inverse kinematics employing a post-accelerated radioactive ion beam (RIB) at the REX-ISOLDE facility. The experiment was performed at an energy of 2.95 MeV/u using a combination of the T-REX particle detectors, the Miniball γ-detection array and a newly-developed delayed-correlation technique as to investigate μs-isomers. Angular distributions of the ground state and multiple excited states in 67Ni were obtained and compared with DWBA cross-section calculations, leading to the identification of positive-parity states with substantial
𝜈
g
9
/
2
(1007 keV) and
𝜈
d
5
/
2
(2207 keV and 3277 keV) single-particle strengths up to an excitation energy of 5.8 MeV. 50% of the
𝜈
d
5
/
2
single-particle strength relative to the
𝜈
g
9
/
2
-orbital is concentrated in and shared between the first two observed
5
/
2
+
levels. A comparison with extended Shell Model calculations and equivalent (3He, d) studies in the region around 9040Zr50 highlights similarities for the strength of the negative-parity pf and positive-parity
g
9
/
2
state, but differences are observed for the
d
5
/
2
single-particle strength.

Authors: J. Diriken, N. Patronis, A.N. Andreyev, S. Antalic, V. Bildstein, A. Blazhev, I.G. Darby, H. De Witte, J. Eberth, J. Elseviers, V.N. Fedosseev, F. Flavigny, Ch. Fransen, G. Georgiev, R. Gernhäuser, H. Hess, M. Huyse, J. Jolie, Th. Kröll, R. Krücken, R. Lutter, B.A. Marsh, T. Mertzimekis, D. Mücher, F. Nowacki, R. Orlandi, A. Pakou, R. Raabe, G. Randisi , P. Reiter, T. Roger, M. Seidlitz, M. Seliverstov, K. Sieja, C. Sotty, H. Tornqvist, J. Van De Walle, P. Van Duppen, D. Voulot, N. Warr, F. Wenander, K. Wimmer

Doi: 10.1016/j.physletb.2014.08.004

Issue number:

Journal: Phys. Lett. B

Page number: 533

Published on: 2014-08-07

Year: