Deuteron production in relativistic heavy ion collisions via stochastic multiparticle reactions

Abstract

We study the deuteron production via the deuteron pion and nucleon catalysis reactions, and , by employing stochastic multiparticle reactions in the hadronic transport approach SMASH for the first time. This is an improvement compared to previous studies, which introduced an artificial fake resonance to simulate these reactions as a chain of reactions. The derivation of the stochastic criterion for multiparticle reactions is presented in a comprehensive fashion and its implementation is tested against an analytic expression for the scattering rate and the equilibrating particle yields in box calculations. We then study Au Au collisions at GeV, where we find that multiparticle collisions substantially reduce the time required for deuterons to reach partial chemical equilibrium with nucleons. Subsequently, the final yield of is practically independent from the number of at particlization, confirming the results of previous studies. The mean transverse momentum and the integrated elliptic flow as a function of centrality are rather insensitive to the exact realization of the reactions.