International comparison of measuring techniques of tritium production for fusion neutronics experiments: Status and preliminary results

A neutronics experiment has been launched in the European fusion technology program on a mock-up of a test blanket module with the objective to validate the capability of nuclear data to predict nuclear responses with qualified uncertainties. In the experiment, the mock-up will be irradiated with a 14-MeV neutron source and the tritium production rate will be measured and compared with the calculated value by neutron cross sections from the European Fusion File. Given the difficulty of performing a reliable measurement of tritium production rate in such experiments, an international benchmark comparison on tritium measurement techniques has been carried out in collaboration between ENEA, TUD/VKTA and also JAERI that has already performed such experiments. The main purpose of the comparison is to establish the reference technique of TPR measurements to be used later in the TBM experiment. Three steps of the comparison procedure are presented in the paper as well as the preliminary results. The implications for the TBM experiment are also discussed.