MULTIFRACTAL ANALYSIS OF CHARGED PARTICLE DISTRIBUTION IN 28Si-Ag/Br INTERACTION AT 14.5A GeV

The multifractal structure of one dimensional charged particle density distribution in 28 Si-Ag / Br interactions at 14.5 GeV per nucleon is investigated by using two different techniques. The experimental measurements are compared with a microscopic transport model of particle production based on the Ultra-relativistic Quantum Molecular Dynamics (UrQMD). Various parameters related to multifractality, for example the Lévy's index, are obtained. Our analysis shows that multifractal structure is present both in the experiment as well as in the simulation. As far as the self-similar nature of the density fluctuation is concerned, there exists, however, a small but definite quantitative difference between the two.

CENTRALITY DEPENDENCE OF NONSTATISTICAL FLUCTUATION IN SINGLE PARTICLE DENSITY DISTRIBUTION IN 32S–Ag/Br INTERACTION AT 200A GeV/c

Nonstatistical fluctuations in the density distribution of shower tracks coming out of 32 S – Ag/Br interaction at an incident momentum of 200A GeV/c, have been characterized by using the intermittency and multifractality techniques. A sample of 32 S – Ag/Br nuclear emulsion events has been partitioned into three subsamples with respect to the shower track multiplicity in such a way that one can roughly estimate the average centrality for each subsample. Thereby, the centrality dependence of a set of relevant intermittency and multifractal issues has been investigated.

Target excitation dependence of degree of multifractality and critical exponent in ultrarelativistic nuclear collision

The target excitation dependence of the degree of multifractality and critical exponent of pions produced for the 16O-AgBr interaction at 60 AGeV has been investigated. To study target excitation dependence, the data for the produced pions were distributed into three sets, depending on the number of grey tracks (ng). The different sets correspond to the different degrees of target excitation. The probability G-moments were used for the analysis in pseudorapidity space. The analysis reveals that the produced particle density distribution possesses multifractal structure for all degrees of target excitation (0 ≤ ng ≤ 3, 4 ≤ ng ≤ 7, and ng ≥ 8). The distribution Levy index and the phase transition critical exponent are calculated. The study indicates the non-thermal phase transition, but it does not show evidence for the second-order phase transition.