Scaling properties of particle density fluctuations at LHC energies

¹ Department of Physics, Institute of Science, Banaras Hindu University - Varanasi 221005, India
² Department of Physics and Electronics, Dr. Rammanohar Lohia Avadh University - Ayodhya 224001, India
³ Department of Physics, Aligarh Muslim University - Aligarh 202002, India
⁴ Discipline of Natural Sciences, PDPM Indian Institute of Information Technology Design & Manufacturing Jabalpur 482005, India
⁵ Department of Physics, Indian Institute of Technology Bombay - Mumbai 400076, India

Received: 30 June 2024
Accepted: 4 September 2024

Abstract

The availability of high-multiplicity events at LHC energies provides a unique opportunity to examine the nature of phase-transition (PT) 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 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, d_q, are observed to increase with the order of the moments q, suggesting the multifractal nature of the charged particle production. The parameter λ_q is found to exhibit a monotonically decreasing trend with the order of the moments but with no clear minima in λ_q 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, shows significant departure from the value ∼1.304, as expected for the Ginzberg-Landau (GL) type second-order PT but exhibits a good level of agreement with the results obtained by other models at LHC energies.