Multiplicity-dependent production of Σ(1385)^± and Ξ(1530)⁰ in pp collisions at √s=13 TeV

The production yields of the Σ(1385)^± and Ξ(1530)⁰ resonances are measured in pp collisions at √s=13 TeV with ALICE. The measurements are performed as a function of the charged particle multiplicity ⟨dN_ch/dη⟩, which is related to the energy density produced in the collision. The results include transverse momentum (pT) distributions, pT-integrated yields, mean transverse momenta of Σ(1385)^± and Ξ(1530)⁰, as well as ratios of the pT-integrated resonance yields relative to yields of other hadron species. The Σ(1385)^±/π^± and Ξ(1530)⁰/π^± yield ratios are consistent with the trend of the enhancement of strangeness production from low to high multiplicity pp collisions, which was previously observed for strange and multi-strange baryons. The yield ratio between the measured resonances and the long-lived baryons with the same strangeness content exhibits a hint of a mild increasing trend at low multiplicity, despite too large uncertainties to exclude the flat behaviour. The results are compared to predictions from models such as EPOS-LHC and PYTHIA 8 with Rope shoving. The latter provides the best description of the multiplicity dependence of the Σ(1385)^± and Ξ(1530)⁰ production in pp collisions at √s=13 TeV.