Strangeness production as a function of charged particle multiplicity in proton-proton collisions
نویسنده
چکیده
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 K0 S , Λ, Λ, Ξ ± and Ω± at mid-rapidity measured as a function of multiplicity in pp collisions at √ s = 7 TeV with the ALICE experiment. Spectral shapes studied both for individual particles and via particle ratios such as (Λ/K0 S ) as a function of pT 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.
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