Low-energy structure of 2766Co39 and 2768Co41 populated through β decay

The low-energy level structures for the neutron-rich Co isotopes at N = 39 and N = 41 are constructed following the beta decay of the respective even-even Fe isotopes. Spin and parity assignments of the lowest energy populated state in Co-66 and Co-68 are consistent with a 1(+) spin and parity assignment and attributed to the coupling of the deformed proton configurations identified in Co-67 and deformed neutron configurations inferred from neighboring Fe isotones. Comparisons along the N = 39 and N = 41 isotonic chains reveal a similarity in the structures of the Co and Mn isotopes.