Multi-strange baryon production in pp, p-Pb and Pb-Pb collisions measured with ALICE

TL;DR

This paper reports measurements of multi-strange baryon production in pp, p-Pb, and Pb-Pb collisions with ALICE, revealing strangeness enhancement, energy dependence, and nuclear modification factors, advancing understanding of quark-gluon plasma signatures.

Contribution

It provides new experimental data on multi-strange baryons across different collision systems and energies, and compares results with thermal model predictions.

Findings

Strangeness enhancement increases with collision centrality and strangeness content.

The yield ratio decreases with increasing collision energy.

Nuclear modification factors differ for multi-strange baryons compared to lighter particles.

Abstract

The production of {\Xi}$^{-}$ and {\Omega}$^{-}$ baryons and their anti-particles in pp, p-Pb and Pb-Pb collisions has been measured by the ALICE Collaboration. These hyperons are reconstructed via the detection of their charged weak-decay products, which are identified through their measured ionisation losses and momenta in the ALICE Time Projection Chamber. Comparing the production yields in Pb-Pb and pp collisions, a strangeness enhancement has been measured and found to increase with the centrality of the collision and with the strangeness content of the baryon; moreover, in the comparison with similar measurements at lower energies, it decreases as the centre-of-mass energy increases, following the trend already observed moving from SPS to RHIC. Recent measurement of cascade and {\Omega} in p-Pb interactions are compared with results in Pb-Pb and pp collisions and with predictions from thermal models, based on a grand canonical approach. The nuclear modification factors for the charged {\Xi} and {\Omega}, compared to the ones for the lighter particles, are also presented.