IJCLab invites applications for a PhD, potentially fully financed, to contribute to the F2-HECK project ``From Few-body to High-Energy antinuclei Collision Kinematics'' between CNRS and CEA lead by the PI of the project Dr. Jean-Christophe David at CEA. F2-HECK aims to connect state-of-the-art ab initio nuclear theory with nuclear simulation code, leveraging complementary expertise within the consortium. F2-HECK develops an ab initio, bottom-up description of low-energy nucleus-antinucleus interactions to enable reliable modeling of cosmic ray signals relevant to dark matter. We will compute scattering, atomic level shifts/widths, and annihilation observables, with a flagship focus on deuteron–antideuteron collisions and extensions to light p-shell nuclei. By separating sequential vs simultaneous annihilation and propagating uncertainties from NN and \bar NN interactions, we will deliver validated nuclear inputs for experiments (PUMA/ALICE) and astroparticle applications. A dedicated work package will transfer these microscopic constraints into the INCL reaction model code to improve antideuteron annihilation and will allow to transition towards reaction mechanisms across a wide range of energy. This two-way theory–simulation loop will provide the nuclear data and modeling tools needed to interpret future cosmic-ray antinuclei searches.