Unveiling the dynamics of nucleosynthesis in relativistic heavy-ion collisions

Abstract

Like nucleosynthesis during the early universe, light nuclei are also produced in relativistic heavy-ion collisions. Although the deuteron ($d$) yields in these collisions can be well described by the statistical hadronization model (SHM), which assumes that particle yields are fixed at a common chemical freezeout near the phase boundary between the quark-gluon plasma and the hadron gas, the recently measured triton (${}^3\text{H}$) yields in Au+Au collisions at $\sqrt{s_{NN}}=7.7-200$ GeV are overestimated systematically by this model. Here, we develop a comprehensive kinetic approach to study the effects of hadronic re-scatterings, such as $\ddot{I}€NN\leftrightarrow \ddot{I}€d$ and $\ddot{I}€NNN\leftrightarrow \ddot{I}{€}^3\text{H}{(}^3\text{He})$, on $d$, ${}^3\text{H}$, and ${}^3\text{He}$ production in these collisions. We find that these reactions have little effects on the deuteron yield but reduce the ${}^3\text{H}$ and ${}^3\text{He}$ yields by about a factor of 1.8 from their initial values given by the SHM. This finding helps resolve the overestimation of triton production in the SHM and provides the evidence for hadronic re-scattering effects on nucleosynthesis in relativistic heavy-ion collisions.

6 pages, 4 figures. arXiv admin note: text overlap with arXiv:2106.12742