Speaker
Description
The microscopic mechanism responsible for the formation of light (anti)(hyper)nuclei in hadron–hadron collisions remains one of the open questions in high-energy nuclear physics. While statistical hadronization and nucleon coalescence models both reproduce measured yields, momentum spectra, and fluctuations in pp, p–A, and A–A collisions at ultra-relativistic energies, they are based on fundamentally different physical assumptions, leading to model-dependent interpretations. In this work, new femtoscopy results on pion–deuteron correlations in pp collisions at √s = 13 TeV, measured by the ALICE experiment, are presented. The correlation function directly probes the residual interaction between pions and nucleons originating from short-lived Δ decays, followed by their coalescence into deuterons. This measurement provides, for the first time, a model-independent demonstration that (anti)deuteron production in ultra-relativistic pp collisions proceeds via nucleon coalescence. The results offer new constraints for the modeling of light- and heavy-nuclei formation in cosmic-ray interactions and dark-matter decay scenarios.
