The 'Ni nucleus has been identified among the products of deep-inelastic reactions of Ni projectiles bombarding '3OTe and~o 'Pb targets. Three new states, including the high-lying 2+ (2033 keV) and the 0.86 ms 5 isomer, indicate a substantial subshell closure at neutron number N = 40. The level structure and the observed very slow E3 transition speed are discussed within the shell model. PACS numbers: 27.50.+e, 21.60.Cs, 23.20.Lv, 25.70.Lm In spherical nuclei the 1g9/2 orbital is distinctly separated in energy from all other single-particle levels. This gives rise to the well established magicity of the neutron and proton numbers N, Z = 50 and points towards a somewhat less pronounced closure at N, Z = 40. For protons the Z = 40 subshell closure is clearly demonstrated by the well known level structure of the 9OZr nucleus [1], for which the lowest excitation is the 1.76 MeV 0+ state, the first 2+ state appears at 2.19 MeV, and the lowest lying particle-hole (p,~2g9t2) excitation produces the longlived 5 isomeric state. The study of similar features in

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