Jayita Ghosh

FRACTAL BEHAVIOR OF NUCLEAR FRAGMENTS IN HIGH ENERGY INTERACTIONS

The multifractal analysis of data on nuclear fragments obtained from 28Si-AgBr interactions at 14.5 A GeV is performed using three different methods (the factorial moments, G-moments and Takagi moments). The generalized fractal dimensions Dq is determined from all these methods. Data reflects multifractal geometry for the nuclear fragments. From the knowledge of Dq, the multifractal specific heat is calculated for this data and also for 16O-AgBr interactions at 60 A GeV and 32S-AgBr interactions at 200 A GeV.

Multiplicity-dependent chaotic pionization in ultra-relativistic nuclear interactions

The fluctuation of spatial patterns from event to event has been investigated by analysing the pionization data of 32S–AgBr interactions at 200 A GeV in terms of a new parameter entropy index, μq, which is a measure of chaotic behaviour in multipion production process. It is observed that the multipion production process becomes more chaotic with the increase of average multiplicities of the final states.

EVIDENCE OF SELF-AFFINE PION MULTIPLICITY FLUCTUATION IN RELATIVISTIC AND ULTRARELATIVISTIC NUCLEAR COLLISIONS

This paper reports a detailed study on self-affine behavior of multiplicity fluctuation in the pionization process at relativistic and ultrarelativistic nuclear collisions. The study was performed over a wide range of energy from 2.1–200 AGeV. The data used are 16O-AgBr interactions at 2.1 AGeV and 60 AGeV, 32S-AgBr interactions at 200 AGeV, 24Mg-AgBr, and 12C-AgBr interactions at 4.5 AGeV. All these data show a clear evidence of self-affine pion production over the entire energy regime.

Evidence of self-affine target fragmentation process in relativistic nuclear collision at a few GeV/n

Self-affine multiplicity scaling is investigated in the framework of two-dimensional factorial moment methodology using the concept of Hurst exponent (H). Investigation on the experimental data of target fragments emitted in 12C–AgBr and 24Mg–AgBr interactions at 4.5 A GeV revealed that best power law behaviour is exhibited at H = 0.5 for 12C initiated interactions indicating self-affine multiplicity fluctuations. But for 24Mg–AgBr interactions it cannot be unambiguously concluded whether the nature of dynamical fluctuations is self-affine or self-similar. The signal of multifractality is observed for both the interactions.

EVIDENCE OF THE NON-THERMAL PHASE TRANSITION IN THE EMISSION OF SLOW TARGET RESIDUE IN 28Si–AgBr INTERACTIONS AT 14.5 AGeV

This paper reports an investigation on the occurrence of the non-thermal phase transition in the target fragmentation of 28Si–AgBr interactions at 14.5 AGeV in azimuthal angle space using the method of factorial moment. Clear evidence of the non-thermal phase transition is obtained.

Factorial correlator study in 16O-AgBr interaction at 60A GeV

An investigation of non-statistical fluctuations in 16 O-AgBr interaction at 60A GeV in terms of factorial correlators is presented. The correlated moments are found to increase with decreasing bin-bin separation D , following a power law.

Void analysis of pions and its multiplicity dependence at Dubna and SPS energies

This paper investigates the multiplicity dependence of void probability scaling of fluctuation of pions (i.e. classifying fluctuation patterns of pions on the basis of their number, ns) for a wide range of projectile energy from 4.5 to 200 A GeV. The study reveals that void probability scaling is dependent on pion multiplicity at all energies. At comparatively lower projectile energy the scaling becomes poor with increase in average multiplicity, however at high energy the scaling is found to be independent of multiplicity.

Multidimensional erraticity analysis in ultra-relativistic nuclear collisions

This work reports a detailed study on multidimensional erraticity analysis on 32S–AgBr interactions at 200 A GeV. A general scaling law between the erraticity moments with phase-space partition number is observed. The analysis reveals the true picture of chaotic pion production.

Void probability scaling in target fragmentation of high energy nucleus-nucleus collisions

This study reports the scaling behaviour of void probability in limited phase space during the emission of slow target fragments in 12C–AgBr and 24Mg–AgBr interactions at 4.5 A GeV. This study will also enable us to check the validity of linked pair ansatz.

Evidence of dynamical fluctuation of target residues in relativistic nuclear interaction at 14.5 AGeV

An analysis of data of target fragments of 28Si-AgBr (at 14.5 AGeV) reveals the existence of emission asymmetry in the azimuthal plane, which is found to depend on the number of target fragments. The comparison with the data of 32S-AgBr (at 200 AGeV) and 16O-AgBr (at 60 AGeV) interactions indicates that emission asymmetry depends on the projectile mass and energy.