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The thermal scattering laws (TSL) take into account the crystalline structure and atomic motions of isotopes bound in materials. This paper presents the CINEL code, which was developed to generate temperature-dependent TSL for solid, liquid and free gas materials of interest for nuclear reactors. CINEL is able to calculate TSL from the phonon density of states (PDOS) of materials under the Gaussian-Incoherent approximations. The PDOS can be obtained by using theoretical approaches (e.g., ab initio density functional theory and molecular dynamics) or experimental results. In this work, the PDOS presented in the ENDF/BVIII.0 and NJOY-NCrystal libraries were used for numerical validation purposes. The CINEL results are in good agreement with those reported in these databases, even in the specific cases of TSL with the newly mixed elastic format. The coding flexibility offered by Python using the JupyterLab interface allowed to investigate limits of physical models reported in the literature, such as a four-site model for UO2, anharmonic behaviors of oxygen atoms bound in a Fm3m structure, texture in Zry4 samples and jump corrections in a roto-translational diffusion model for liquid water. The use of graphic processing units (GPU) is a necessity to perform calculations in a few minutes. The performances of the CINEL code is illustrated with the results obtained on actinide oxides having a Fm3m structure (UO2, ThO2, NpO2 and PuO2), low enriched fuel (UMo), cladding (Zry4) and moderators (H2O with a specific emphasis on ice).

A new heating and gas treatment line for Thermo-Desorption Spectrometry (TDS) of noble gases (He, Ne, Ar, Kr, and Xe) is presented. It was built with the primary objective to offer advanced temperature controls and capabilities while working in a cold environment. By choosing a high-power continuous wave laser as the heating source and using a proportional-integral-derivative controller system, TDS of noble gases can now be performed with fast and highly steady heating ramps (e.g., less than 1 °C deviation from the set point for ≤1 °C s -1 ramps). Sample temperature over 2000 °C can also routinely be reached, with limited heating of the sample support and the sample chamber, offering the possibility to have several samples awaiting in the ultra-high vacuum chamber. We also present the development efforts made to increase temperature homogeneity of the heated sample while limiting the contact with the sample holder. Recent results acquired with this TDS setup on krypton thermal diffusion in uranium dioxide (UO 2 ) as a function of O 2 additions are also presented as an application example.

We present the raw data obtained from release rate at 1300°C of Xe and Kr implanted in UO 2 , related to [1]. We performed different sample preparation (polishing treatment) on polycrystalline and monocrystalline UO 2 . Ion implantation were performed at various fluences between 9.5 × 10 10 to 5 × 10 14 i/cm 2 in UO 2 samples. Release rate of Xe and Kr are obtained at 1300°C under vacuum from desorption experiments performed on the PIAGARA plateform at the CENBG (Centre d'Etudes Nucléaires de Bordeaux-Gradignan). Since we made a variety of samples depending on multiple parameters (sample type, sample preparation, ion implantation type and fluence), these data represent a serious amount of work that could be saved for the scientific community that might use them for other purposes such as burst modelling., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 Published by Elsevier Inc.)