MCNPX calculation of the reactivity worth of actinides OSMOSE samples

Improving neutronic prediction is a very important step in designing advanced reactors and reactor fuel. There are three main critical reactor facilities of the CEA Cadarache. These reactor facilities are EOLE, MINERVE and MASURCA. The MINERVE reactor is used within the frame work of what is known as OSMOSE project. The OSMOSE program aims at improving neutronic predictions of advanced nuclear fuels through measurements in the MINERVE reactor on samples containing separated actinides. In the present work, the reactivity worth of OSMOSE samples have been calculated using the most recent Monte Carlo N Transport code MCNPX using the most recent nuclear cross-section data library ENDF/B-VII. The calculations are applied to the three core configurations R1-UO2, R2-UO2 and R1-MOX. The present work is performed to improve and/or measure the degree of validity of the previous obtained results of the REBUS and DRAGON codes. Also, our study is extended to include the experimental results for the sake of comparison. The comparison between the previously calculated values using DRAGON and the present results for the effective multiplication factor keff has a deviation less than ±0.3% for the three core configurations. Furthermore, the results of the reactivity worth of the present work show a good agreement with the experimental results within a relative error less than ±8.2%.