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arXiv · 2605.11275

Freeze-out model of light nuclei formation in heavy-ion collision transport

Oleh Savchuk·Pawel Danielewicz·William Lynch·Jérôme Margueron
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Abstract

Cluster production plays an important role in heavy-ion collisions at intermediate beam energies, where light nuclei contribute substantially to final-state yields and to other observables that are used to infer the nuclear equation of state. In this letter, we propose a new approach for clustering that combines dynamical transport and thermal cluster production for mid-rapidity particles. The resulting hybrid coarse-graining model matches nucleon and light-cluster descriptions at freeze-out while properly accounting for thermal non-uniformity and collective transport in the hot, strongly interacting systems created in heavy-ion collisions. To illustrate the capabilities of this model, yields at 4~fm impact parameter, spectra and elliptic flows at 7.4~fm ($20\text{--}30\%$ centrality) are predicted at mid-rapidity for semi-peripheral Au$+$Au collisions at an incident energy of $E_\text{lab}=1.23~A\mathrm{GeV}$.

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Oleh Savchuk, Pawel Danielewicz, William Lynch, Jérôme Margueron. 2026-05-11. Freeze-out model of light nuclei formation in heavy-ion collision transport. https://arxiv.org/abs/2605.11275

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