Multiplicity dependence of pi , K, and p production in pp collisions at sqrt{s} = 13\xa0TeV

Abstract

This paper presents the measurements of pi ^{pm }, mathrm {K}^{pm }, text {p} and overline{mathrm{p}} transverse momentum (p_{text {T}}) spectra as a function of charged-particle multiplicity density in proton–proton (pp) collisions at sqrt{s} = 13 text {TeV} with the ALICE detector at the LHC. Such study allows us to isolate the center-of-mass energy dependence of light-flavour particle production. The measurements reported here cover a p_{text {T}} range from 0.1 to 20 text {GeV}/c and are done in the rapidity interval |y|<0.5. The p_{text {T}}-differential particle ratios exhibit an evolution with multiplicity, similar to that observed in pp collisions at sqrt{s} = 7 text {TeV}, which is qualitatively described by some of the hydrodynamical and pQCD-inspired models discussed in this paper. Furthermore, the p_{text {T}}-integrated hadron-to-pion yield ratios measured in pp collisions at two different center-of-mass energies are consistent when compared at similar multiplicities. This also extends to strange and multi-strange hadrons, suggesting that, at LHC energies, particle hadrochemistry scales with particle multiplicity the same way under different collision energies and colliding systems.