Strangeness production as a function of charged particle multiplicity in proton-proton collisions

TL;DR

This study investigates how the production of various identified particles varies with event multiplicity in high-energy proton-proton collisions, revealing phenomena similar to those in larger collision systems.

Contribution

It provides the first detailed measurement of identified particle production as a function of multiplicity in pp collisions at 7 TeV, highlighting similarities with larger collision systems.

Findings

Hyperon production increases more rapidly than non-strange hadrons with multiplicity.

Spectral shapes and particle ratios evolve with event multiplicity.

Qualitative similarities observed between pp, p-Pb, and Pb-Pb collision phenomena.

Abstract

Recent measurements performed in high-multiplicity proton-proton (pp) and proton-lead (p-Pb) collisions have shown features that are reminiscent of those observed in lead-lead (Pb-Pb) collisions. These observations warrant a comprehensive measurement of the production of identified particles. We report on the production of \allparts at mid-rapidity measured as a function of multiplicity in pp collisions at $\sqrt{s}$ = 7 TeV with the ALICE experiment. Spectral shapes studied both for individual particles and via particle ratios such as ($\Lambda/K^{0}_{S}$) as a function of $p_{T}$ exhibit an evolution with event multiplicity and the production rates of hyperons are observed to increase more strongly than those of non-strange hadrons. These phenomena are qualitatively similar to the ones observed in p-Pb and Pb-Pb collisions.