In heavy-ion collisions (A$-$A) at the CERN Large Hadron Collider (LHC) energies, a strongly coupled Quark Gluon Plasma (QGP) is produced, giving rise to collective phenomena whose signatures can be retrieved in final state hadronic observables. Recent observations suggest the presence of collective phenomena in small systems like pp collisions. Ongoing analyses therefore try to identify whether a unified description of the pp, p$-$A and A$-$A data can be established.
The integrated yield ratios to pion yields show an increasing trend at low charged-particle multiplicity that tends to saturate at higher multiplicities. The behaviour is dependent on the strangeness content of the particle species and is totally independent of the collision system and energy (multiplicity-driven particle production). Furthermore, a blast wave analysis shows how strong radial gradients are also present in p$-$Pb collisions at LHC energies.
Hydrodynamic and recombination models are tested against the measured hadron spectral shapes at low and intermediate transverse momenta.