Scaling Properties of Particle Density Fluctuations at LHC Energies

Abstract The availability of high multiplicity events at LHC energies provides a unique opportunity to examine the nature of phase transition in heavy-ion collisions. Within the framework of HYDJET++ model, a systematic study of particle density fluctuations in narrow phase-space bins in Pb-Pb collisions at √sNN = 2.76 and 5.02 TeV energies is performed using the method of scaled factorial moments (SFM). The findings reveal the presence of intermittency in the 2-dimensional (2D) phase space distribution of charged particles at the LHC energies. The anomalous fractal dimensions, dq, are observed to increase with the order of the moments q, suggesting the multifractal nature of the charged particle production. The parameter λqis found to exhibit a monotonically decreasing trend with the order of the moments but with no clear minima in λq values. Furthermore, the value of the critical exponent is estimated and compared with those predicted by other models reported at RHIC and LHC energies. The value of the critical exponent, ν, obtained in the present study, show significant departure from the valueLandau (GL) type second-order phase transition but exhibits a good level of agreement with the∼1.304, as expected for the Ginzbergresults obtained by other models at LHC energies.