Speaker
Description
Over the last 5 years, the Jet Energy loss Tomography with a Statistically and Computationally Advanced Program Envelope (JETSCAPE) collaboration has constructed and publicly released an extensive framework to design, build and test event generators for high energy heavy-ion collisions. The physics of these collisions involves many aspects, such as the initial state of incoming nuclei, the thermalization of the deposited energy, the viscous fluid expansion, hadronic cascade, and the propagation of hard jets and/or rare particles through the evolving medium. The study of such an elaborate system requires a modular and extensible simulator. The current publicly available code base contains a framework that allows users to use existing physics modules, or extend functionality by adding new modules, and Bayesian routines to test the veracity of model choices. State-of-the-art default modules can be used to carry out simulations of the formation of the quark-gluon plasma (QGP) in nuclear collisions and study jet quenching in these plasmas. Parameters introduced in this factorized multi-stage approach are constrained by Bayesian methods in comparison with a subset of experimental data. Posterior distributions can then be used to make rigorous comparisons between theory and experiment. I will outline recent results from this exciting new approach in high energy nuclear physics, and sketch the evolving picture of bulk and hard dynamics in heavy-ion collisions.
