Shell structure of even-even nickel isotopes containing twenty to forty neutrons

Bespalova, O. V.*; Boboshin, I. N.*; Varlamov, V. V.*; Ermakova, T. A.*; Ishkhanov, B. S.*; Klimochkina, A. A.*; Komarov, S. Yu.*; Koura, Hiroyuki   ; Romanovsky, E. A.*; Spasskaya, T. I.*

Shell parameters of even-even nickel isotopes involving twenty to forty neutrons are analyzed, and the results of this analysis are presented. A detailed comparison of the results obtained by calculating, on the basis of the mean-field model with the Koura-Yamada potential and the dispersive optical potential, single-particle energies of proton and neutron subshells with experimental data on the isotopes Ni and with evaluated data on the neutron-deficient isotopes Ni is performed. The Koura-Yamada potential predicts correctly special features in dependence of single-particle energy and are useful in evaluating sub-shell energies on unstable nuclei.