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

Abstract

The production yields of the Sigma(1385)(+/-) and.(1530)(0) resonances are measured in pp collisions at root s = 13TeV with ALICE. The measurements are performed as a function of the charged-particle multiplicity dN(ch)/d eta , which is related to the energy density produced in the collision. The results include transverse momentum (p(T)) distributions, p(T)-integrated yields, mean transverse momenta of Sigma(1385)(+/-) and.(1530)(0), as well as ratios of the p(T)-integrated resonance yields relative to yields of other hadron species. The Sigma(1385)(+/-)/pi(+/-) and Xi(1530)(0)/ pi(+/-) 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 with 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 Sigma(1385)(+/-) and Xi(1530)(0) production in pp collisions at root s = 13TeV.