Investigating High Spin States in ⁵⁹Co and ⁵⁹Ni

A fusion evaporation reaction, ¹⁴C on ⁴⁸Ti was carried out at the John Fox Laboratory, FSU to populate high spin states in ⁵⁹Co and ⁵⁹Ni. The evaporation channels, 2np and 3n from the compound nucleus, ⁶²Ni lead to the ⁵⁹Co and ⁵⁹Ni being studied. In the shell model picture, ⁵⁹Co has a ground state of 7/2^- because of an unpaired valence proton in the 1f_7/2 level while ⁵⁹Ni has a ground state of 3/2^- because of an unpaired neutron in the 2p_3/2 level. The current experiment has established the presence of several positive states of high spin in both nuclei, arising from cross shell excitations from the fp shell to the g_9/2 orbital. The level scheme of ⁵⁹Co has been expanded to around 11MeV with spin 31/2⁺ assigned. The highest negative parity state experimentally determined is 27/2^- at around 9.5MeV. For ⁵⁹Ni, the highest state is still at 37/2⁺, though at lower energy than the previous study on ⁵⁹Ni. This work has extended the negative states of 59Ni to 31/2^- at around 15MeV. In the high spin states of both nuclei, we have configurations allowing for rotation bands because of excitations of particles into the g_9/2 orbital and presence of holes in the f_7/2 orbitals. Detailed results and comparison with shell-model calculations will be presented.