EMMI Workshop: Light-ion collisions 2026

The LHCb experiment offers a unique ion physics programme through both collider and fixed-target configurations, providing access to a broad range of collision energies and nuclear systems. Heavy-flavour production is a powerful probe of nuclear matter, allowing the study of both cold nuclear matter effects and the properties of the medium created in high-energy nuclear collisions. The combination of collider and fixed-target data enables a systematic exploration of collision systems spanning different sizes and energies, offering a unique opportunity to search for the onset of quark-gluon plasma signatures.

During Run 3, LHCb collected its first samples of light-ion collisions, including pO, OO, and NeNe, enabling the first measurements of prompt D$^0$ mesons and $\Upsilon$ production in these systems. Complementing the collider programme, the SMOG2 fixed-target programme provides proton- and ion-induced collisions at intermediate centre-of-mass energies, extending the exploration of QCD into a previously relatively unexplored energy regime. Recent measurements include J/$\psi$, $\psi$(2S), and D$^0$ production in fixed-target collisions as well as hydrodynamic studies with charged -particle flow.

This contribution will present the first heavy-flavour results from the Run 3 light-ion programme together with recent highlights from the fixed-target programme, illustrating how the complementary collider and fixed-target measurements at LHCb provide new insight into the evolution of heavy-flavour production and the emergence of quark-gluon plasma signatures across a broad range of collision systems and energies.