Hanbury-Brown-Twiss analysis and dynamical correlations

We test the applicability of the Hanbury-Brown-Twiss theory of bosonic enhancement for the analysis of heavy ion reactions. The correlation function is calculated in a solvable model. We find that the analysis in terms of the ratio of like-sign to unlike-sign pairs is more reliable and more stable than in terms of the ratio of pairs to single mesons. We also compare our exact results with the predictions obtained in a classical treatment of the source function, like the one that is used to extract correlation functions from cascade type simulations. In spite of agreement for extreme choices of the parameters of our model, the results of the approximation deviate strongly from the exact correlation function for Physical Noticed choices. We thus call into question the use of classical approximations for the analysis of reactions in which the final state is produced by a cascade of resonance decays