Production of strange hadrons in jets and underlying events in pp and p–Pb collisions with ALICE

Abstract

Abstract The production of strange ( K S 0 , Λ) and multi-strange (Ξ± and Ω±) hadrons in jets and underlying events in pp and p–Pb collisions is studied with ALICE at the LHC. Transverse momentum (p T) differential density distribution of particles produced in a jet is compared to that of inclusive particle production and that in underlying events. The particle yield ratios of ( Λ + Λ ¯ ) / 2 K S 0 and ( Ξ − + Ξ ¯ + ) / ( Λ + Λ ¯ ) as a function of p T are also investigated in jets and underlying events. The production of the multi-strange hadrons, Ξ± and Ω±, and the corresponding ratio in jets and underlying events are measured for the first time. The p T-differential density distribution of hadrons associated with hard scattering decreases slower than that for inclusive production. The baryon-to-meson and baryon-to-baryon ratios measured in jets exhibit clear differences from values obtained from the inclusive spectra in the intermediate p T range. The p T distribution of strange hadrons produced in jets is also studied in pp collisions at s = 13 TeV and s = 7 TeV and in p–Pb collisions at s NN = 5.02 TeV . The p T spectra of particle produced in jets are independent of collision systems and collision energies. No apparent collision energy and collision system dependence is observed for the particle yield ratios of ( Λ + Λ ¯ ) / 2 K S 0 and ( Ξ − + Ξ ¯ + ) / ( Λ + Λ ¯ ) associated with energetic jets. These new results are compared to PYTHIA 8 event generator. The ( Λ + Λ ¯ ) / 2 K S 0 ratio are generally reproduced by the model, but large discrepancies between data and PYTHIA simulations are observed for ( Ξ − + Ξ ¯ + ) / ( Λ + Λ ¯ ) .