Speaker
Description
The main goal of the ALICE experiment is to study the physics of strongly interacting matter, including the properties of the quark-gluon plasma (QGP). The enhanced production of strange hadrons with respect to non-strange hadrons was historically considered as one of the signatures of QGP formation during the evolution of the system created in heavy-ion collisions. The excellent tracking and particle identification capabilities of the ALICE experiment allow the reconstruction of multi-strange baryons via their weak decay channels over a large range of transverse momentum. Recent measurements performed in high-multiplicity proton-proton (pp) collisions have shown features that are reminiscent of those observed in lead-lead (Pb-Pb) collisions. The microscopic origin of this phenomenon is still not fully understood: is it related to soft particle production or to hard scattering events, such as jets?
To separate strange hadrons produced in jets from those produced in soft processes, the angular correlation between high-$p_\mathrm{T}$ charged particles and strange hadrons has been exploited. The near-side jet yield and the out-of-jet yield of $\mathrm{K^0_S}$ and $\Xi^\pm$ have been studied as a function of the multiplicity of charged particles produced in pp collisions at $\sqrt{s}=13$ TeV.
The results suggest that strangeness enhancement in pp collisions is driven by out-of-jet processes, which give the dominant contribution to strange particle production.
