decay of 72Co and microsecond isomers in even-mass neutron-rich nickel isotopes.

A new excited state at 2164 keV has been identified in ⁷²Ni with tentative spin and parity of 4⁺ based on comparison to shell model calculations. This level is suggested to be populated via the β-decay of an isomeric state in ⁷²Co, and is postulated to be one of the key states that play a role in the disappearance of isomers in Ni. The known low-energy levels in ⁷²Ni are compared with results of shell model calculations using the NR78 interaction to follow the seniority of the observed states. In addition, the half-life of the 8⁺ isomer in ⁷⁶Ni has been measured as 630(90) ns and the full cascade of transitions from this isomer has been verified experimentally in this work. [ABSTRACT FROM AUTHOR]