Direct measurement of 60Co and 125I activity by the sum-peak method in PTKMR-BATAN

The sum-peak method was successfully applied to the determination of the activity of 60Co and 125I sources measured by HPGe and well-type NaI(Tl) detectors in PTKMR-BATAN. The result of the 60Co activity agrees with the activity value measured by using a calibrated ionization chamber within a range of about 0.35–0.5% and the activity result of 125I agrees with the activity value measured using the photon–photon coincidence method within a range of 0.05–0.26%. - Highlights: • Sum-peak method applied to activity determination of 60Co and 125I. • Measured by well-type NaI(Tl) and HP(Ge) detectors. • Results agree (<0.5% and <0.3%) with those from calibrated ionization chambers