Fast-Neutron Bombardment ofNi64and the Decay ofFe61

Abstract
A 6.15±0.06-min activity, which has been assigned to the decay of Fe61, has been produced as the result of bombardment of nickel enriched in Ni64 with 15-19-MeV neutrons. The decay scheme has been studied by β, γ, βγ, and γγ counting techniques using plastic scintillators, NaI(Tl) crystals, and a Ge(Li) detector. Evidence was found for levels in Co61 at 1.028±0.005, 1.206±0.005, 1.327±0.005, 1.650±0.015, and 1.995±0.020 MeV.