Summing-coincidence corrections with Geant4 in routine measurements by γ spectrometry of environmental samples

• True-coincidence-summing corrections were calculated using Geant4.
• Simulated corrections were validated using experimental data.
• A second validation using real samples with natural radionuclides was also done.

In this work, we describe a method to quantitatively evaluate true-coincidence-summing effects by making use of the Geant4 toolkit, which incorporates an emulation of the radionuclide disintegration scheme. To check the capabilities of the method, we firstly validated the simulated corrections using the ones obtained experimentally for radionuclides such as 60Co, 152Eu and 133Ba. Secondly, we evaluated the effect of summing corrections of some radionuclides included in two intercomparison exercises to conclude that the results were improved when utilising the method described here.