Analysis of gamma-ray dosimetry experiments for the validation of the JHR nuclear heating calculation scheme

The design process of the Jules Horowitz Reactor (JHR), which will be dedicated to studies of material radiation damage, requires an accurate knowledge of the neutron and gamma heating in order to control the sample thermal conditions under irradiation. A nuclear heating calculation scheme called HORUS3D/P has been developed by the CEA Nuclear Energy Division. The accuracy attainable in nuclear heating problems with the HORUS3D/P calculation scheme and the available nuclear data has not yet been clearly assessed and needs to be tested in appropriate experiments. That is why a set of integral, small-scale experiments of gamma heating measurements, called ADAPh, are planned in EOLE and MINERVE critical assemblies at the CEA Cadarache facility. In the first phase of the ADAPh experiments, different kinds of thermo-luminescent dosimeters (TLD) are inserted in the MOX core of EOLE. In the second phase, TLD and micro-ionization chambers are inserted in the UO2 core of MINERVE. This paper presents the analysis of the first phase: the specific calculational methodology is described and the experimental uncertainties are estimated. The comparison between calculated and measured absorbed doses in TLD shows that calculation constantly underestimates by about 25% the measurements with 15% (k=2) of total uncertainties. The systematic bias observed could be attributed to a lack of nuclear data used. (authors)