A coalescence afterburner for antinuclei production in hadronic collisions with Monte Carlo generators.

The advent of the LHC as antimatter factory has enabled an unprecedented effort to measure the production of light (anti)nuclei from pp to heavy-ion collisions, providing input for a detailed study of nucleosynthesis in high-energy interactions. The production of these bound states, however, is not modelled in commonly employed event generators. To fill this gap, we developed a coalescence afterburner to be used within Monte Carlo generator inputs to model the production of light (anti)nuclei in hadronic interactions on an event-by-event basis. In this contribution, the PYTHIA8 event generator is preliminarily tuned to describe (anti)proton yields as measured at the LHC. The PYTHIA8 input is fed to a Wigner function-based coalescence afterburner that forms a nucleus when two or more nucleons are close in phase space, depending on the momentum distribution of the nucleons, the nucleus wave function, and the size of the nucleon emitting source. The results are discussed in comparison to ALICE data and in perspective, for applications of the model to the estimate of the flux of cosmic antinuclei for indirect dark matter searches with space-based experiments like AMS and GAPS.