Exploratory study of actinium-225 production capabilities in research reactors and particle accelerators

This postdoctoral research project will examine various methods of producing the medical radioisotope 225Ac. These methods will involve irradiating 226Ra using either a material testing reactor (such as the Jules Horowitz Reactor) or a particle accelerator (such as a cyclotron or a rhodotron). The study will determine the optimal conditions for producing 225Ac, including the type and energy of the incident particles, the target material used, and the corresponding production yields, as well as the quantity of contaminants generated.
The first part of the work will involve modelling the irradiation characteristics in research reactors and particle accelerators. This modelling will be carried out at the Department of Reactor Studies at the IRESNE Institute, at the CEA Cadarache site. Monte Carlo simulations using TRIPOLI4®, GEANT4 and PHITS – developed by the CEA, CERN and JAEA, respectively – will be employed to model the JHR and the particle accelerators.
The second part of the project will be carried out in close collaboration with several CEA laboratories. These laboratories will host the postdoctoral researcher on an ad hoc basis to support them through the subsequent stages of the project.
The CHICADE facility in Cadarache is responsible for designing the targets. The proposed work involves identifying the main steps for manufacturing the targets by electrodeposition, starting with a stock of 226Ra-containing material. If possible, a feasibility study will also be conducted on non-irradiated targets with the same properties (cerium/barium model material).
In collaboration with the DRMP units responsible for modelling the thermomechanical aspects of the targets, the proposed work will also involve conducting a feasibility study on the ion irradiation of a model target at a facility such as JANNuS-Saclay or GANIL.

Decomposition of Fission Fragment Energy from Microscopic Approaches to Provide Input Data for the FIFRELIN Code

The FIFRELIN code (FIssion FRagment Evaporation modeLINg), developed since 2009 at the CEA, simulates the formation and decay of nuclear fission fragments. It contributes to the enrichment of the European nuclear data library JEFF, which is used for reactor simulations. The calculation proceeds in two steps: the generation of fission fragments (with their physical properties), followed by their decay using a Monte Carlo Hauser-Feshbach approach. At the moment of scission into two fragments, the total energy is split between kinetic energy (TKE) and excitation energy (TXE). The TXE is further divided into deformation energy and intrinsic excitation energy, which govern the emission of neutrons and photons. Accurate knowledge of both TXE and TKE is essential to improve FIFRELIN’s performance. Microscopic theoretical approaches (such as Hartree-Fock-Bogoliubov and the Generator Coordinate Method) are used and developed within DES to provide theoretical input supporting evaluated nuclear data. This postdoctoral position aims to use and enhance these models to gain a more detailed understanding of nuclear properties at scission. The desired candidate has several years of experience (3 years or more) in nuclear mean-field theory (such as Hartree-Fock-Bogoliubov, relativistic mean-field, etc.) or in the generator coordinate method.