Entropy and multifractality in ring-like and jet-like events produced in 11.6A GeV/c $^{197}$Au-AgBr collisions

Abstract

Physical quantities such as, entropy, dimensions and multifractal characteristics of multiplicity distributions of charged particles produced in $^{197}$Au-AgBr collisions are examined and the findings are compared with the predictions of Monte Carlo model URQMD (Ultra-Relativistic Quantum Molecular Dynamics) and HIJING (Heavy Ion Jet INteraction Generator) and also with the results reported earlier in hadron-hadron and nucleus-nucleus collisions at different energies. Based on their azimuth distribution, the charged particles produced within narrow-bins exhibit two kinds of substructures, namely, ring-like and jet-like substructures. Thus, on applying the suitable criteria the two different types of events are identified and analyzed separately. It is observed that the maximum entropy production occurs around a narrow mid-rapidity region. The analyses of ring-like and jet-like events suggest that the entropy production is much larger in ring-like events as compared to that in jet-like events. Furthermore, Renyi's order-q information entropy is used to estimate the multifractal specific heat and to construct the spectrum of scaling indices. The findings reveal that the value of multifractal specific heat is higher in ring-like events as compared to that in jet-like events. The studies of generalized dimension and multifractal spectrum indicate that the multifractality is rather, more pronounced in ring-like events as compared to jet-like events. Various features of the experimental data are noticed to be nicely reproduced by the URQMD model