Trajectum: A Model for Large Ion Collisions

A Bayesian analysis of Heavy Ion Collisions with Trajectum

We introduce a model for heavy ion collisions named trajectum, which includes an expanded initial stage with a variable free streaming velocity and a hydrodynamic stage with three varying second order transport coefficients.We describe how to obtain a gaussian emulator for this 20-parameter model and show results for key observables.This emulator can be used to obtain bayesian posterior estimates on the parameters, which we test by an elaborate closure test as well as a convergence study.We employ the optimal values of the parameters found in [1] to perform a detailed comparison to experimental data from pb pb and collisions.