Search

We estimate the fraction of energy of the quark gluon plasma (QGP) fluids in high-energy proton–proton and nuclear collisions with the dynamical core–corona initialisation (DCCI) model. The fraction of the QGP fluids turn out to be the key to interpret the strangeness enhancement in high-multiplicity small colliding systems.

We investigate whether the quark gluon plasma (QGP) is created in small colliding systems from analyses of various hadron yields and their ratios in proton-proton (p+p), proton-lead (p+Pb) and lead-lead (Pb+Pb) collisions at LHC energies. Recently, the ALICE Collaboration reports enhancement of yield ratio of multi-strange hadrons to charged pions as a function of multiplicity at mid-rapidity. Motivated by these results, we develop the dynamical core-corona initialization framework and find that our results describe tendencies of the ALICE data especially for multi-strange hadrons. These results indicate that the QGP is partly formed in high multiplicity events in small colliding systems., Comment: 4 pages, 5 figures; contribution to the proceedings of the 8th International Conference on Quarks and Nuclear Physics (QNP2018), Tsukuba, November 13-17, 2018

We develop the dynamical core-corona initialization framework as a phenomenological description of the formation of quark gluon plasma (QGP) fluids in high-energy nuclear collisions. Using this framework, we investigate the fraction of the fluidized energy to the total energy and strange hadron yield ratios as functions of multiplicity and scrutinize the multiplicity scaling of hadron yield ratios recently reported by the ALICE Collaboration. Our results strongly indicate that the QGP fluids are partly formed even at the averaged multiplicity for nonsingle diffractive p+p events., 14 pages, 10 figures; Title changed. Published version

We investigate the enhancement of yields of strange and multi-strange baryons in proton-proton (p+p), proton-lead (p+Pb) and lead-lead (Pb+Pb) collisions at the Large Hadron Collider (LHC) energies from a dynamical core-corona initialization model. We first generate partons just after the collisions by using event generators. These partons dynamically generate the quark gluon plasma (QGP) fluids through the source terms in the hydrodynamic equations. According to the core-corona picture, this process tends to happen where the density of generated partons is high and their transverse momentum is low. Some partons do not fully participate in this process when they are in dilute regions or their transverse momentum is high and subsequently fragment into hadrons through string fragmentation. In this framework, the final hadrons come from either chemically equilibrated fluids as in the conventional hydrodynamic models or string fragmentation. We calculate the ratio of strange baryons to charged pions as a function of multiplicity and find that it monotonically increases up to $dN_{\mathrm{ch}}/d\eta \sim 100$ and then saturates above. This suggests that the QGP fluids are \textit{partly} created and that their fraction increases with multiplicity in p+p and p+Pb collisions at LHC energies., Comment: 6 pages, 2 figures; published version

We build the dynamical core–corona initialisation model to perform gradual and multiplicity-dependent generation of quark-gluon plasma (QGP) fluids in high energy nuclear collisions. This model reasonably describes the multiplicity dependence of particle yield ratios measured by ALICE Collaboration. We also find that non-zero fraction of energy in non-single diffractive p+p collision events is converted to the QGP fluid even at the average multiplicity.