Measurement of the production of (anti)nuclei in p-Pb collisions at $\sqrt{s_{\rm NN}} = 8.16$ TeV

TL;DR

This paper reports on measurements of (anti)nuclei production in p-Pb collisions at 8.16 TeV, analyzing coalescence parameters and yield ratios to understand particle formation mechanisms across different multiplicities.

Contribution

It provides new experimental data on (anti)nuclei production in p-Pb collisions and compares coalescence and statistical models, favoring the coalescence approach.

Findings

Coalescence parameters $B_2$ and $B_3$ evolve smoothly with multiplicity.

Deuteron-to-proton ratio favors coalescence over statistical models.

Yields of (anti)deuterons and (anti)$^3$He are reported as functions of multiplicity.

Abstract

Measurements of (anti)proton, (anti)deuteron, and (anti)$^3$He production in the rapidity range $-1<y< 0$ as a function of the transverse momentum and event multiplicity in p-Pb collisions at a center-of-mass energy per nucleon-nucleon pair $\sqrt{s_{\rm NN}} = 8.16$ TeV are presented. The coalescence parameters $B_2$ and $B_3$, measured as a function of the transverse momentum per nucleon and of the mean charged-particle multiplicity density, confirm a smooth evolution from low to high multiplicity across different collision systems and energies. The ratios between (anti)deuteron and (anti)$^3$He yields and those of (anti)protons are also reported as a function of the mean charged-particle multiplicity density. A comparison with the predictions of the statistical hadronization and coalescence models for different collision systems and center-of-mass energies favors the coalescence description for the deuteron-to-proton yield ratio with respect to the canonical statistical model.