Jet Quenching at RHIC from Discovery to Precision Tool

The effects of jet quenching were first observed at RHIC and announced by the experiments in 2003. These early results were evidence of energetic particles losing energy due to the formation of a hot dense medium known as the quark-gluon plasma (QGP). Originating from energetic particles produced in the earliest stages of the collision, jets are excellent probes of the QGP. Measurements of jet quenching have evolved significantly from the suppression of high momentum hadrons to sophisticated jet reconstruction and grooming techniques. In particular, newer jet measurements at RHIC explore the pathlength dependence of the energy loss, the medium’s response to this energy and the role of the size of the colliding nuclei.



This talk will highlight jet quenching related observables from PHENIX, STAR and sPHENIX. In 2025, sPHENIX, which was described in the US Nuclear Science Long Range plan as essential for completing the scientific mission of RHIC, collected its high statistics Au+Au dataset which will provide a wealth of new jet quenching results. sPHENIX, which started collecting data in 2023, was specifically designed to make precision jet measurements in RHIC’s 200 GeV collisions and already has initial jet measurements. Planned measurements at sPHENIX will address open questions such as how energy loss depends on the flavor of the initial parton and will use updated tools to quantify the substructure of jets and separate the jets from the underlying event produced in these heavy ion collisions. In addition, the latest RHIC measurements will complement ongoing LHC jet measurements and challenge theoretical models to describe energy loss in the QGP formed at the lower collisions energies as well as for lower momentum jets.