Validation and improvement of curium radiochronometry to determine the model discharge date of spent nuclear fuels

This study validates and improves the Cm radiochronometry method developed to determine the model discharge date of nuclear spent fuels based on a three isotopes system, specifically the ²⁴⁴Cm/²⁴⁶Cm and ²⁴⁴Cm/²⁴⁵Cm ratios change since discharge time. Six spent fuel samples with continuous irradiation histories were used. After Cm separation from the matrix, the Cm isotopes were measured by accelerator mass spectrometry using one of the samples as internal standard for normalization. The mean average deviation from the known fuel discharge date improved from 3.3 ± 2.8 to 2.7 ± 2.6 yr when using spent fuel with continuous irradiation. (author)