Speaker
Description
Nuclear data benchmarking is often oriented towards criticality experiments. While such measurements represent a crucial pillar of the process providing evaluators with insight on the quality of fuel-related nuclear data, these experiments are often less informative about other nuclear data. Local measurements can be considered to gather the needed complementary information. Such experiments serve a twofold purpose: they can be tailored to be sensitive to different nuclear data, while being ideal characterization measurements that help gain trust in the whole complex of experimental and model results produced at a research facility. Fission rate traverse experiments (i.e., spatially resolved fission rate measurements from the active core to the reflector) are useful observables in this context.
We present 235U, 237Np and 232Th fission rate traverse measurements performed with fission chambers in the VENUS-F fast reactor within the VALUE project. The results of 235U are relevant for the epithermal and fast spectrum, while those of 237Np and 232Th are interesting for the information they give on the fast spectrum. The purity of the latter fission chambers allows us to achieve reliable results up to the core reflector. There, the significant epithermal spectrum tail could otherwise induce significant fissions in common impurities (e.g., 235U and 239Pu) with a risk of spoiling the measurements. Precision in the fission chamber axial positioning is achieved thanks to its motorized movement. On top of allowing for full axial scan of the reactor core, this setup allows for rather flexible choice of the experiment location in the core lattice and eases the data processing thanks to the simultaneous acquisition of detector position and count rate.
As a main goal of this contribution, we present experimental results with the aim of providing the community with new data. The presented measurements are compared to observations in other fast (BFS ) and thermal (DIMPLE) systems. Calculation-to-experiment comparison for these measurements reflects the knowledge of the spectrum in one of the experimental channels used for oscillation experiments in VENUS-F. The presented results are then relevant on the side of nuclear data verification while contributing to the definition of a solid characterization ground for the future development of oscillation experiments in VENUS-F.
| Session | Microscopic and Integral Measurements |
|---|