The ability of nuclear models to accurately predict the rich phenomenology emerging in nuclei (whether for fundamental purposes or nuclear data applications) is conditioned by the possibility to construct a systematically improvable theoretical framework, i.e. with controlled approximations and estimation of associated uncertainties and biases. This is the goal of so called ab initio methods, which rely on two steps:
1 - The construction of an inter-nucleon interaction in adequation with the underlying theory (quantum chromodynamics) and adjusted in small systems, following effective field theory paradigm.
2 - The resolution of nuclear many-body problem to a given accuracy (for structure or reactions observables). This provides predictions in all nuclei of interest and includes the uncertainty propagation stemming from the interaction model up to nuclear data predictions.

This PhD thesis mostly deals with Step 1. The goal of the thesis is to construct a family of ab initio interactions by developing a new adjustment procedure of the low energy constants (including the evaluation of covariances for sensitivity analysis). The adjustment will include structure data but also reaction observables in light systems. This will open the door to a new evaluation of p+n->d+gamma cross sections (which have large uncertainties despite their importance for neutronics applications) in the context of state-of-the-art effective fields theories.

The thesis will be done in collaboration between CEA/IRESNE (Cadarache) and IJCLab (Orsay), the PhD student will spend 18 months in each laboratories. Professional perspectives are academic research and R&D labs in nuclear physics.