Jet-like correlations with respect to K⁰ₛ, and Λ (Λ̄) in pp and central Pb–Pb collisions at √ˢɴɴ =5.02 TeV

Abstract

Two-particle correlations with K⁰ₛ, Λ / Λ̄, and charged hadrons as trigger particles in the transverse momentum range 8< Pᴛ,trig <16 GeV/c, and associated charged particles within 1< Pᴛ,assoc <8 GeV/ c, are studied at midrapidity in pp and central Pb–Pb collisions at a centre-of-mass energy per nucleon–nucleon collision √ˢɴɴ = 5.02 TeV with the ALICE detector at the LHC. After subtracting the contributions of the flow background, the per-trigger yields are extracted on both the near and away sides, and the ratio in Pb–Pb collisions with respect to pp collisions (Iᴀᴀ) is computed. The per-trigger yield in Pb–Pb collisions on the away side is strongly suppressed to the level of IAA ≈ 0.6 for Pᴛ,assoc > 3 GeV/ c as expected from strong in-medium energy loss, while an enhancement develops at low Pᴛ,assoc on both the near and away sides, reaching Iᴀᴀ ≈ 1.8 and 2.7 respectively. These findings are in good agreement with previous ALICE measurements from two-particle correlations triggered by neutral pions (π⁰–h) and charged hadrons (h–h) in Pb–Pb collisions at √ˢɴɴ = 2.76 TeV. Moreover, the correlations with K0S mesons and Λ / Λ̄ baryons as trigger particles are compared to those of inclusive charged hadrons. The results are compared with the predictions of Monte Carlo models.