Enhanced collectivity in 74Ni
/ Authors
N. Aoi, S. Kanno, S. Takeuchi, H. Suzuki, D. Bazin, M. Bowen, C. Campbell, J. Cook, D. Dinca, A. Gade
and 12 more authors
T. Glasmacher, H. Iwasaki, T. Kubo, K. Kurita, T. Motobayashi, W. Mueller, T. Nakamura, H. Sakurai, M. Takashina, J. R. Terry, K. Yoneda, H. Zwahlen
/ Abstract
Abstract The neutron-rich nucleus 74Ni was studied with inverse-kinematics inelastic proton scattering using a 74Ni radioactive beam incident on a liquid hydrogen target at a center-of-mass energy of 80 MeV. From the measured de-excitation γ rays, the population of the first 2+ state was quantified. The angle-integrated excitation cross section was determined to be 14(4) mb. A deformation length of δ = 1.04 ( 16 ) fm was extracted in comparison with distorted wave theory, which suggests that the enhancement of collectivity established for 70Ni continues up to 74Ni. A comparison with results of shell model and quasi-particle random phase approximation calculations indicates that the magic character of Z = 28 or N = 50 is weakened in 74Ni.
Journal: Physics Letters B