BR2 reactor coupled MCNPX and mure simulations for the solid experiment (antineutrino detection)

Large quantities of antineutrinos are produced in a reactor due to beta decays of the fission products. The detection of these antineutrinos associated to reactor simulations could provide a method to assess both the thermal power and the evolution of the core fuel composition. One of the aims of the SoLid experiment located at the BR2 research reactor (SCK-CEN, Mol) is to investigate the ability of reactor monitoring with an antineutrino detector based on ⁶LiF:ZnS and the use of such a detector for safeguards purpose. A detailed simulation of the BR2 reactor is needed to calculate the antineutrino spectrum emitted by the core for each cycle, i.e. for a given fuel loading map and operation history. A Monte-Carlo depletion code: MURE (MCNP Utility for Reactor Evolution) has been used for a few years in order to compute the antineutrino energy spectrum emitted by a PWR reactor but also research reactors. A detailed MCNPX/CINDER90 3-D simulation of the fission rates distribution in the BR2 core will be coupled with the MURE code. In this paper, the MURE code and the on-going developments for the BR2 simulation will be presented. The results of a benchmark performed between MURE and MCNPX/CINDER90 on the depletion calculation of a fuel assembly will also be discussed. (author)