Speaker
Description
The development of radioactive ion beams (RIB) in the mid-eighties has enabled the exploration of regions of the nuclear landscape away from the valley of stability, uncovering nuclei with unexpected features. Halo nuclei exhibit among the most peculiar structures in the nuclear landscape. Unlike most nuclei, they have a very large matter radius compared to their isobars, that can be explained by the presence of one or two loosely-bound nucleons away from the others, forming a diffuse halo around a compact core. These clusterized objects have therefore challenged the usual picture of a nucleus as a compact object. Due to their short life-time, exotic nuclei are often studied through reactions, in which they collide with a target. Various kinds of reactions, e.g. transfer, breakup or one-neutron knockout, are studied at RIB, such as FRIB. The latter corresponds to the removal of one or two valence nucleons from the projectile on a light target. It is often favored for low-intensity beams, because, thanks to the fragile nature of halo nuclei, it exhibits a high cross section. In this talk, I will show how effective field theory descriptions of halo projectiles integrated within a few-body reaction formalism efficiently bridge ab initio predictions and one- neutron knockout observables. The comparison of the predicted cross sections with experimental data therefore provides a stringent test for these state-of-the-art nuclear structure models. I will then present a sensitivity analysis of one-neutron knockout cross sections of more deeply-bound neutron-rich nuclei to their neutron distributions, indicating that these observables could be used to extract information about their neutron skin thickness.
