Nuclear Data Sheets for A=64

Abstract

The evaluated experimental data are presented and evaluated for 13 known nuclides of mass 64 (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se). For each nuclide, the best values combining all available data are recommended for spectroscopic properties. No excited states have been identified in ⁶⁴Ti, ⁶⁴As, and ⁶⁴Se. Only one excited state in ⁶⁴V as an isomer, and three in ⁶⁴Cr have been identified. Data for excited states in ⁶⁴Mn, ⁶⁴Fe, and ⁶⁴Co remain limited. ⁶⁴Ni, ⁶⁴Cu, and ⁶⁴Zn are the most studied nuclides through various reactions and decays, followed by ⁶⁴Ga and ⁶⁴Ge. In the opinion of the evaluators, there are several incomplete or discrepant aspects of the high-spin portion of the level scheme for ⁶⁴Zn above ≈5 MeV excitation which need to be resolved in further experiments using large γ-detector arrays. The decay schemes of ⁶⁴Ti β⁻, ⁶⁴As ε and ⁶⁴Se ε are unknown, while very little information is available for ⁶⁴V β⁻ and ⁶⁴Cr β⁻. The decay schemes of ⁶⁴Mn β⁻, ⁶⁴Fe β⁻, ⁶⁴Co β⁻ and ⁶⁴Ge ε are somewhat better known, but still considered incomplete by evaluators. The decay scheme of ⁶⁴Ga ε decay is known in detail, however there is the possibility of additional levels populated above 4713 keV, as the Q(ε) value is 7171 keV. The β⁻, β⁺ and ε decay modes of ⁶⁴Cu are well known, as this radionuclide is of great importance in applications, for example, as a dosimeter for neutron flux determination in nuclear reactors, and as a radiopharmaceutical for positron emission tomography (PET). This work supersedes earlier full evaluations of A=64 by 2007Si04, 1996Si12, 1991Si03, 1979Ha35 and 1974Au04.