Investigating the cluster production mechanism with isospin triggering: Thermal models versus coalescence models

Abstract

Isospin triggering allows to distinguish coalescence from thermal production of light clusters in heavy ion collisions. Triggering on $Y(\ddot{I}{€}^{-})-Y(\ddot{I}{€}^{+})$ allows to select very neutron or proton rich final states. The deuteron (cluster) production with coalescence ($d\propto n\cdot p$) leads then to an inverse parabolic dependence of the deuteron yield on $\hat{I}”Y_{\ddot{I}}€$. In contrast, in a thermal model, cluster production is independent on $\hat{I}”Y_{\ddot{I}}€$. The observation of a maximum deuteron (cluster) yield as function of $\hat{I}”Y_{\ddot{I}}€$ provides confirmation of the coalescence mechanism.

6 pages, 5 figures, version accepted and published by Physical Review C