Precision energy determination of gamma-rays from the 66Ga(β++ϵ)66Zn decay

Abstract The energies of 29 γ-rays from the 66 Ga( β + + ϵ ) 66 Zn decay have been measured with Ge(Li) detectors, of which one in a Compton suppression shield. Energy calibration standards were provided by 46 Sc, 56 Co, 65 Zn, 110 Ag m and 124 Sb radioactive sources. The resulting excitation energies of 18 66 Zn levels, obtained in a least-squares fit, then provide the energies for 26 strong lines ( E γ = 0.83−4.81 MeV) with a final precision of better than 10 ppm. Of particular importance are the five E γ = 3.76−4.81 MeV lines, which now can serve as calibration standards in this hitherto uncovered high-energy region.