Multi-strange particle measurements in 7 TeV proton-proton and 2.76 TeV PbPb collisions with the ALICE experiment at the LHC

TL;DR

This paper reports measurements of multi-strange particle production in proton-proton and lead-lead collisions at the LHC, revealing discrepancies with models and providing insights into particle yields across different collision systems and energies.

Contribution

It provides new experimental data on multi-strange baryon yields at 7 TeV pp and 2.76 TeV PbPb collisions, highlighting model deficiencies and advancing understanding of strange particle production.

Findings

Data exceeds predictions from PYTHIA models.

Yields vary with collision centrality in PbPb.

Comparison across energies shows energy dependence of production.

Abstract

The production of charged multi-strange particles is studied with the ALICE experiment at the CERN LHC. Measurements of the central rapidity yields of $\Xi^-$ and $\Omega^-$ baryons, as well as their antiparticles, are presented as a function of transverse momentum ($p_\mathrm{t}$) for inelastic pp collisions at $\sqrt{s}=7$ TeV and compared to existing measurements performed at the same and/or at lower energies. The results are also compared to predictions from two different tunes of the PYTHIA event generator. We find that data significantly exceed the production rates from those models. Finally, we present the status of the multi-strange particle production studies in Pb-Pb at $\sqrt{s_{NN}}=2.76$ TeV performed as a function of collision centrality.