Multiplicity dependence of light nuclei production at LHC energies in the canonical statistical model

TL;DR

This paper uses the Canonical Statistical Model to analyze how the production of light nuclei depends on charged pion multiplicity at LHC energies, showing a monotonic increase and saturation in yield ratios that align with experimental data.

Contribution

It introduces a detailed analysis of light nuclei yields using the CSM with exact charge conservation, incorporating rapidity considerations and variable freeze-out temperatures.

Findings

Yield ratios increase with multiplicity and saturate at grand-canonical limits.

Exact charge conservation and temperature variation improve data agreement.

Results qualitatively match ALICE experimental measurements.

Abstract

The statistical model with exact conservation of baryon number, electric charge, and strangeness - the Canonical Statistical Model (CSM) - is used to analyze the dependence of yields of light nuclei at midrapidity on charged pion multiplicity at the LHC. The CSM calculations are performed assuming baryon-symmetric matter, using the recently developed Thermal-FIST package. The light nuclei-to-proton yield ratios show a monotonic increase with charged pion multiplicity, with a saturation at the corresponding grand-canonical values in the high-multiplicity limit, in good qualitative agreement with the experimental data measured by the ALICE collaboration in pp and Pb-Pb collisions at different centralities and energies. Comparison with experimental data at low multiplicities shows that exact conservation of charges across more than one unit of rapidity and/or a chemical freeze-out temperature which decreases with the charged pion multiplicity improves agreement with the data.