Hypernuclei, dibaryon and antinuclei production in high energy heavy ion collisions: Thermal production vs. coalescence

We study the production of (hyper-)nuclei and dibaryons in most central heavy ion collisions at energies of Elab=1-160 A GeV. In particular we are interested in clusters produced from the hot and dense fireball. The formation rate of strange and non-strange clusters is estimated by assuming thermal production from the intermediate phase of the UrQMD-hydro hybrid model and alternatively by the coalescence mechanism from a hadronic cascade model. Both model types are compared in detail. For most energies we find that both approaches agree in their predictions for the yields of the clusters. Only for very low beam energies, and for dibaryons including Ξ's, we observe considerable differences. We also study the production of anti-matter clusters up to top RHIC energies and show that the observation of anti-4He and even anti-4ΛHe is feasible. We have found a considerable qualitative difference in the energy dependence of the strangeness population factor RH when comparing the thermal production with the coalescence results.