K$^{0}_{\rm S}$- and (anti-)$\Lambda$-hadron correlations in pp collisions at $\sqrt{s} = 13$ TeV

TL;DR

This study investigates strange hadron correlations in proton-proton collisions at 13 TeV to understand jet fragmentation and the transition between bulk and hard particle production, comparing results with theoretical models.

Contribution

It provides the first detailed measurement of K$^{0}_{ m S}$- and $ ext{Lambda}$-hadron correlations at 13 TeV, exploring strangeness effects and event multiplicity dependence.

Findings

Near- and away-side peak yields vary with trigger particle type and event multiplicity.

Results show differences between data and PYTHIA 8, EPOS LHC predictions.

Insights into strangeness production mechanisms in high-energy pp collisions.

Abstract

Two-particle azimuthal correlations are measured with the ALICE apparatus in pp collisions at $\sqrt{s} = 13$ TeV to explore strangeness- and multiplicity-related effects in the fragmentation of jets and the transition regime between bulk and hard production, probed with the condition that a strange meson (K$^{0}_{\rm S}$) or baryon ($\Lambda$) with transverse momentum $p_{\rm T} > 3$ GeV/c is produced. Azimuthal correlations between kaons or $\Lambda$ hyperons with other hadrons are presented at midrapidity for a broad range of the trigger ($3 < p_{\rm T}^{\rm trigg} < 20$ GeV/$c$) and associated particle $p_{\rm T}$ (1 GeV/$c$ $< p_{\rm T}^{\rm assoc} < p_{\rm T}^{\rm trigg}$), for minimum-bias events and as a function of the event multiplicity. The near- and away-side peak yields are compared for the case of either K$^{0}_{\rm S}$ or $\Lambda$($\overline{\Lambda}$) being the trigger particle with that of inclusive hadrons (a sample dominated by pions). In addition, the measurements are compared with predictions from PYTHIA 8 and EPOS LHC event generators.