ALICE data in the framework of the Color String Percolation Model

Abstract

Possible phase transition of strongly interacting matter from hadron to a quark-gluon plasma state have in the past received considerable interest. The clustering of color sources provides a framework of the partonic interactions in the initial stage of the collisions. The onset of de- confinement transition is identified by the spanning percolation cluster in 2D percolation. In the present work we have analyzed the transverse momentum spectra of charged particles in high multiplicity pp collisions at LHC energies $\sqrt{s}=05.02$ and 13 TeV published by the ALICE Collaboration using the Color String Percolation Model (CSPM). For heavy ions $PbPb$ at $\sqrt{^s{NN}}$ = 2.76 and 5.02 TeV along with $X_eX_e$ at $\sqrt{^s{NN}}$ = 5.44 TeV have been analyzed. The thermodynamical quantities, the temperature, energy density, and the shear viscosity to en- tropy density ratio (η/s) are obtained. It was observed that the inverse of (η/s) represents the trace anomaly ∆ = (ε − 3P)/$T^4$ . Results are in agreement with the Lattice Quantum Chromo Dynamics(LQCD) simulations. Thus the clustering of color sources has a clear physical basis although it cannot be deduced directly from QCD.