Baryon preclustering at the freeze-out of heavy-ion collisions and light-nuclei production

TL;DR

This paper investigates quantum effects on nucleon clustering and light-nuclei formation near the QCD critical point in heavy-ion collisions, introducing novel semiclassical methods and proposing experimental measurements to detect baryon preclustering.

Contribution

It develops new semiclassical flucton methods at finite temperature and applies them to nucleon configurations, providing insights into light-nuclei production mechanisms near the QCD critical point.

Findings

Identification of quantum effects influencing nucleon clustering

Proposal of new experimental measurements for light-nuclei ratios

Highlighting the role of four-nucleon excitations in final nuclei yields

Abstract

Following the idea of nucleon clustering and light-nuclei production in relativistic heavy-ion collisions close to the QCD critical-end point, we address the quantum effects affecting the interaction of several nucleons at finite temperature. For this aim we use the $K$-harmonics method to four-nucleon states ($\alpha$ particle), and also develop a novel semiclassical "flucton" method at finite temperature, based on certain classical paths in Euclidean time, and apply it to two- and four-particle configurations. To study possible effects on the light-nuclei production close to the QCD critical point, we also made such calculations with modified internuclear potentials. For heavy-ion experiments, we propose new measurements of light-nuclei multiplicity ratios which may show enhancements due to baryon preclustering. We point out the special role of the $\mathcal{O}(50)$ four-nucleon excitations of $\alpha$-particle, feeding into the final multiplicities of $d,t$, $^3$He and $^4$He, and propose to directly look for their two-body decays.