Collective phenomena study in small systems using the bulk of particle production in high-multiplicity pp collisions at s =13 TeV with ALICE

The heavy-ion collisions (A--A) at the Large Hadron Collider (LHC) energies have confirmed the production of the quark-gluon plasma (QGP), a new state of nuclear matter where quarks and gluons are deconfined. The light-flavour hadrons (, K, p), constitute the bulk of the produced particles, carry useful information of the collision geometry, collective behaviour and thermal property of the QGP. The measurements of light-flavour hadron production in small collision systems (pp and p--A) at the LHC energies have shown the onset of collective phenomena (e. g. radial flow and long-range correlations) that resemble what is typically observed in nucleus-nucleus collisions and attributed to the formation of a deconfined system of quarks and gluons. The new results of the identified light-flavour particle production measured in high-multiplicity triggered pp collisions at s=13~TeV of ALICE Run 2 will be presented in search of collective behaviour in small collision systems. The transverse momenta p ₓ-spectra of the identified particles show hardening at the mid-p ₓ. The mean transverse momenta (p ₓ) are shown as a function of charged-particle multiplicity. The ratios of p ₓ-spectra and the ratios of the integrated yields of kaon- and proton-to-pion are also presented and compared with published results.