(Anti)nucleosynthesis in heavy-ion collisions and (anti)nuclei as "baryonmeter" of the collision

TL;DR

This paper investigates the production of light (anti)nuclei in heavy-ion collisions, introducing new fluctuation measurements and ratios to distinguish between competing models and precisely determine the baryon chemical potential.

Contribution

It presents the first measurement of antideuteron number fluctuations and uses antinuclei-to-nuclei ratios to accurately measure the baryon chemical potential in heavy-ion collisions.

Findings

First measurement of event-by-event antideuteron fluctuations.

Antinuclei-to-nuclei ratios provide precise $$ measurements.

Results help distinguish between statistical and coalescence models.

Abstract

The production mechanism of light (anti)nuclei in heavy-ion collisions has been extensively studied experimentally and theoretically. Two competing (anti)nucleosynthesis models are typically used to describe light (anti)nuclei yields and their ratios to other hadrons in heavy-ion collisions: the statistical hadronization model (SHM) and the nucleon coalescence model. The possibility to distinguish these phenomenological models calls for new experimental observables. Given their large baryon number, light (anti)nuclei have a high sensitivity to the baryon chemical potential ($\mu_{\rm B}$) of the system created in the collision. In this talk, the first measurement of event-by-event antideuteron number fluctuations in heavy-ion collisions is presented and compared with expectations of the SHM and coalescence model. In addition, the antinuclei-to-nuclei ratios are used to obtain a measurement of $\mu_{\rm B}$ in heavy-ion collisions with unprecedented precision.