Relativistic hydrodynamics of partially stopped baryonic matter

Relativistic hydrodynamics including final-state interactions is used for a detailed description of the experimental data on particle spectra of sulphur-sulphur collisions at 200A GeV from the NA35 Collaboration. Under the assumption of thermalization of the entire detected baryonic matter it is found that a consistent reproduction of both pion and proton spectra requires strong stopping as an initial condition for the expanding fireball. The results from these calculations are then used to extract a transverse radius which includes also contributions from the decay of unstable particle resonances. Its value is found to be rapidity dependent within the range of 3–4 fm, which agrees with experimental results from Bose-Einstein correlations. In addition, the analysis of the strange particle distribution indicates chemical equilibrium for ${\mathit{K}}^0$ and Λ particles.