Ultra-relativistic heavy-ion collisions create a system of deconfined quarks and gluons known as the quark–gluon plasma (QGP). Among other particles, a large number of light nuclei such as the deuteron, triton, helium-3, helium-4 and their corresponding antinuclei are produced, and can be measured with very good precision by the ALICE experiment at the LHC thanks to its excellent tracking and particle-identification capabilities via specific energy loss and time-of-flight measurements. Considering that the binding energies of light (anti)nuclei do not exceed a few MeV, it is not clear how such fragile objects can survive the hadron gas phase created after the phase transition from the QGP to hadrons, where particles rescatter with a typical momentum transfer in excess of 100 MeV. The production mechanism of light (anti)nuclei in these collisions is still not understood and is under intense debate in the scientific community. Constraining models of light antinuclei production is also important for predicting the backgrounds to indirect dark-matter searches using cosmic rays, as performed by experiments in space and in hot-air balloons, for which light antinuclei are promising signals.
Details are in the link to CERN Courier article: https://cerncourier.com/a/fragile-light-nuclei-flow-through-freeze-out/