Speaker
Description
Measurements of azimuthal flow and multi-particle correlations in heavy-ion collisions are typically attributed to a collective expansion of the system created in these collisions that is driven by relativistic hydrodynamics. Surprisingly, similar measurements in small collision systems, such as pp and p--Pb collisions, show striking similarities to the corresponding measurements in heavy-ion collisions. However alternative explanations based on initial state dynamics are able to describe many characteristic features of these measurements. In this contribution, a review of recent experimental highlights on collectivity effects observed in small systems will be presented. These results will be discussed in the context of existing phenomenological models.
