Coalescence, the thermal model and multi-fragmentation: The energy and volume dependence of light nuclei production in heavy ion collisions

Abstract

We present results of a phase space coalescence approach within the UrQMD transport and -hybrid model for a very wide range of beam energies from SIS to LHC. The coalescence model is able to qualitatively describe the whole range of experimental data with a fixed set of parameters. Some systematic deviations are observed for very low beam energies where the role of feed down from heavier nuclei and multi-fragmentation becomes relevant. The coalescence results are mostly very close to the thermal model fits. However, both the coalescence approach as well as thermal fits are struggling to simultaneously describe the triton multiplicities measured with the STAR and ALICE experiment. The double ratio of $tp/d^2$, in the coalescence approach, is found to be essentially energy and centrality independent for collisions of heavy nuclei at beam energies of ${\mathrm{E}}_{\mathrm{lab}}>10A$ GeV. On the other hand the clear scaling of the $d/p^2$ and $t/p^3$ ratios with the systems volume is broken for peripheral collisions, where a canonical treatment and finite size effects become more important.

10 pages, 9 figures, version accepted for publication. J. Phys. G: Nucl. Part. Phys (2022)

References in corpus (8)

• Systematics of central heavy ion collisions in the 1A GeV regime
• Hypernuclei, dibaryon and antinuclei production in high energy heavy ion collisions: Thermal production vs. Coalescence
• Beam energy dependence of (anti-)deuteron production in Au+Au collisions at RHIC
• Formation of hypermatter and hypernuclei within transport models in relativistic ion collisions
• Cluster and hyper-cluster production in relativistic heavy-ion collisions within the Parton-Hadron-Quantum-Molecular-Dynamics approach
• Multiplicity Scaling of Light Nuclei Production in Relativistic Heavy-Ion Collisions
• Formation of hypernuclei in heavy-ion collisions around the threshold energies
• Light nuclei in the hadron resonance gas

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