Simulating fission fragments for advanced energy applications

Abstract This study explores the possibility of usinga neutron source that fissions a 235U fissile thin layer, with the function of covering a tank full of light gas. By using this methodology it is possible to exploit the energy released by the reaction and of the same fission products for various applications (e.g. spatial propulsion, hybrid reactors etc.) which are not analysed in this work. A dedicated Monte Carlo model simulating fission events in a 235U target layer is presented in the first part of the paper. The model characterizes each event by a set of key parameters of the produced Fission Fragments (FF), specifically focused on their energy distribution. The model demonstrates its accuracy by reproducing experimental distributions of critical parameters involved in the fission process. In the second part of this paper, these parameters are compared with established nuclear transport codes to ensure consistency and at the same time an initial analysis of the behavior of FFs in a physical structure is performed. This structure, designed as a thin slab containing a support structure and a light gas, represents a practical step for designing a containment tank for energy collection. The analysis also investigates the interaction of FFs with the different materials and, in particular their energy deposition patterns by using SRIM code and Geant 4. This work then lays the groundwork for further investigation into the use of FFs for energy transfer applications, potentially contributing to the development of innovative propulsion systems.