Longitudinal dynamics of large and small systems from a 3D Bayesian calibration of RHIC collision data

by Dr Matthew Luzum (Sao Paulo University)

Thursday 29 Jan 2026, 11:00 → 12:00 Europe/Amsterdam

Veltman Center

I'll present results from a comprehensive Bayesian analysis of 3D dynamics of ultrarelativistic nuclear collisions of large and small systems, performed by the JETSCAPE Collaboration using measurements from the PHENIX, STAR, PHOBOS, and BRAHMS collaborations spanning nearly two decades of RHIC operations. A 3+1D hybrid hydrodynamic model was calibrated using a large set of measurements from Au+Au and d+Au collisions, and compared to additional observables and additional p+Au and 3He+Au collision systems. I highlight the additional constraints on the initial stages and QGP evolution provided by rapidity-dependent measurements, as well as the importance of rapidity-dependent dynamics even in nominally "mid-rapidity" observables. In particular, I address the apparent differences between the STAR and PHENIX $v_2$ and $v_3$ measurements in small systems. I further point out potential tension in the simultaneous description of certain observables and what it means for the simulation model that was used, and give a perspective on future analyses.