Speaker
Description
The PHENIX experiment at the Relativistic Heavy Ion Collider has carried out a broad and systematic program to study strongly interacting matter over a wide range of collision systems and beam energies. Although PHENIX completed data taking in 2016, its high-statistics data sets continue to provide important constraints on the properties of the quark-gluon plasma, the role of initial-state and cold-nuclear-matter effects, and the emergence of collectivity in small and large collision systems.
In this talk, we will present recent PHENIX highlights relevant to QCD matter under extreme conditions. We will discuss selected measurements of electromagnetic probes, heavy flavor, quarkonia, strangeness production, and identified hadrons in $p$+$p$, small-system, and $A$+$A$ collisions at RHIC energies. These measurements provide complementary sensitivity to different stages of the collision evolution, from initial-state nuclear effects and particle production mechanisms to the hot and dense medium formed in heavy-ion collisions. Particular emphasis will be placed on observables such as nuclear modification factors, azimuthal anisotropies, particle yields, and system-size and multiplicity dependence, which together constrain parton energy loss,
heavy-quark transport, hadronization mechanisms, and collective dynamics.
We will also discuss how the latest PHENIX results connect measurements across collision systems, beam energies, rapidity regions, and particle species. These results demonstrate that the PHENIX legacy data remain an active source of quantitative constraints on QCD matter at RHIC energies. They provide a coherent experimental foundation for understanding the formation and properties of strongly interacting matter, while offering important reference points and complementary constraints for ongoing analyses of recently collected sPHENIX data.