ON UNCERTAINTIES IN THE MANGANESE SULPHATE BATH TECHNIQUES

The manganese sulphate bath is a globally recognized method for determining emission of neutrons from radionuclide since 1959. In combination with the measurement of neutron emission anisotropy, this method is standardly used for the primary standardization of dosimetry quantities of neutron radiation. To achieve results at the metrology level, it is essential to have all quantities which contribute to the overall uncertainty properly determined and contributing uncertainty minimized. This paper is focused on the quantification of the main uncertainty sources for in-house developed manganese bath. In previous analyses, the final uncertainty of neutron emission rate was <1%, which was considered as a target value. Nevertheless, the relative change from reference values was relatively high and out of this uncertainty. This relative change raised questions about the accuracy of contributed parameters, like vessel volume, concentration of MnSO4 or computational model. Therefore, this paper focuses on determination and re-evaluation of these parameters with corresponding uncertainties.