Simulations of dynamic pion production in 60 and 200 GeV collisions of 16O + 197Au

The authors have investigated collision of 16O with 197Au at bombarding energies of 60 and 200 GeV/N in the laboratory frame. Their hydrodynamics-based 3-D model, with a modified gamma-law equation of state, includes detailed dynamic pion production and propagation. A comparison of hydrodynamic simulations with and without the inclusion of pions shows that including the pion channel yields results which more closely reproduce the experimental data. The authors show direct comparisons of several predicted observables with experimental measurements made over various pseudorapidity ranges. In general, they find that while their overall energy agreement with calorimetry experiments is good, and their predicted spatial distributions are in fair agreement with experimental data, their model produces pions which are to energetic and too few in balancing proportions. The authors results indicate that most of the emitted (measured) pions emerge from the cooler surface, and not from the hot, dense interior of the hadronic composite