Delta and pion abundances in hot dense nuclear matter and the nuclear equation of state

Delta and pion abundances in hot dense nuclear matter are calculated self-consistently within a relativistic mean-field model for different equations of state. The density of deltas turns out to be much more sensitive to the effective masses of the baryons than to the stiffness of the equation of state. The results are compared to experimental pion yields from intermediate-energy nucleus-nucleus collisions. The influence of deviations from thermal momentum distributions for the baryons is estimated. (orig.)