Disintegration rate and gamma ray emission probability per decay measurement of 123I

A series of 123I measurements have been carried out in a 4π(eA,X)–γ coincidence system. The experimental extrapolation curve was determined and compared to Monte Carlo simulation, performed by code ESQUEMA. From the slope of the experimental curve, the total conversion coefficient for the 159 keV total gamma transition, α159, was determined. All radioactive sources were also measured in an HPGe spectrometry system, in order to determine the gamma-ray emission probability per decay for several gamma transitions. All uncertainties involved and their correlations were analyzed applying the covariance matrix methodology and the measured parameters were compared with those from the literature.

► Standardization of I-123 was carried out in a coincidence system.
► The experimental extrapolation curve was compared to Monte Carlo simulation.
► Gamma emission probability per decay was determined for I-123.
► HPGe gamma ray efficiency was calculated by MCNPX and compared with the experiment.