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This paper presents an analysis on fractality of compound hadrons (pions + protons) and shower particles produced in heavy ion interactions initiated by 12C and 24Mg beams at incident energy 4.5A GeV and 32S beam at incident energy 200A GeV. G-moments analysis in emission angle (cos θ) space reveals multifractality in both compound hadrons and pion emission process. The degree of multifractality has been assessed using the Levy stability index. Moreover this analysis also suggests nonthermal phase transition in multiparticle production for both cases. [ABSTRACT FROM AUTHOR]

The search for genuine two-particle dynamical correlations among the target evaporated slow particles in 12C-AgBr and 24Mg-AgBr interactions at 4.5 AGeV and 28Si-AgBr interactions at 14.5 AGeV in the emission angle space has been carried out using the method of normalized factorial cumulant moments. The analysis reveals the presence of genuine two-particle dynamical correlations among the target fragments in 12C-AgBr, 24Mg-AgBr, and 28Si-AgBr interactions. The correlations among the target evaporated slow particles are found to decrease with an increase in mass and energy of the projectile beam. Utilisant la méthode normalisée des cumulants factoriels, nous avons complété une recherche des vraies corrélations dynamiques à deux particules parmi les particules lentes évaporées de la cibles dans l'angle d'émission, pour les réactions 12C-AgBr et 24Mg-AgBr à 4.5 GeV et 28Si-AgBr à14.5 GeV. L'analyse révèle de vraies corrélations dynamiques à deux particules dans les fragments de cible des réactions 12C-AgBr et 24Mg-AgBr et 28Si-AgBr. Nous observons que ces corrélations diminuent avec l'augmentation de la masse et de l'énergie du projectile. [ABSTRACT FROM AUTHOR]

Nakamura and Kudo proposed a scaling form for charged particle pseudorapidity distributions on the basis of scaling in the mean hypothesis. This scaling form was tested primarily for hadron-hadron interaction data. But no attempt was made to verify this for hadron-nucleus interaction which offers unique opportunity to learn about the space-time structure of a strongly interacting process. In view of this we report an analysis of p-AgBr interaction data at 400 GeV/c and 200 GeV/c, π--AgBr interaction data at 200 GeV/c and 350 GeV/c to test its (Nakamura-Kudo scaling) validity in hadron-nucleus interaction. In all cases the data show a remarkable agreement with the scaling behavior of Nakamura and Kudo. [ABSTRACT FROM AUTHOR]

We perform a Lévy index analysis of relativistic shower particles produced in the interactions of 32S nuclei at 200A GeV with nuclear emulsion using the results of factorial moment Fq in two-dimensional anisotropic (η - ϕ) space. We carry out the same investigation for target fragments produced in 32S-AgBr interactions at 200A GeV energy for both events in emission angle space and azimuthal angle space. The analysis reveals that for pions the value of Lévy index μ is 1.491 ± 0.025 for ring-like events and μ ~ 2.004 ± 0.054 for jet-like events which indicates different degree of multifractality. In case of target fragments jet-like events show a value of μ ~ 1.871 ± 0.010 whereas ring-like events yields an unphysical value (μ > 2) the implication of which need to be explored. [ABSTRACT FROM AUTHOR]

This paper presents new data on void analysis of target residues in ultrarelativistic nucleus–nucleus interaction. The study reveals a set of interesting observations. Void probability shows a scaling behavior at high energy (32S–AgBr interactions at 200 A GeV) in both forward and backward hemisphere. Whereas such behavior is absent at low energy (16O–AgBr interactions at 60 A GeV) in backward hemisphere. [ABSTRACT FROM AUTHOR]

The target excitation dependence of the higher order cumulant correlation of pions is studied in the present work in the framework of void probability scaling. The data set of pions produced for 16O–AgBr interactions at 2.1 AGeV and 32S–AgBr interactions at 200 AGeV was divided into three sets depending upon the number of grey tracks ng. The different sets of ng correspond to different degrees of target excitation. Analysis was carried out for each set in different pseudorapidity intervals. For the lower projectile energy the void probability scaling is observed only for low target excitation for all pseudorapidity intervals. For the comparatively higher projectile energy, scaling is observed for all pseudorapidity intervals and all target excitation. In other words, for higher projectile energy, scaling is almost independent of the target excitation. The results are interpreted from the point of view of the two source model of particle production. [ABSTRACT FROM AUTHOR]

This paper reports the observation of some peculiar ring-like events in ultra relativistic nuclear interactions (the 32S–AgBr interaction at 200 A GeV and the 16O–AgBr interaction at 60 A GeV). These events have been analysed in the light of Čerenkov gluon radiation as proposed by Dremin. Also the value of the refractive index of the nuclear matter is calculated. The analysis shows values of refractive index different from that revealed in normal nuclear matter. PACS Nos.: 25.75.–q, 24.60.Ky, 12.40.Ee [ABSTRACT FROM AUTHOR]

In this paper non-thermal phase transition for the target fragments of lepton–nucleus interactions at (420±45) GeV is studied in the framework of two-dimensional factorial moment methodology using the concept of Hurst exponent (H) to take care of anisotropic phase space. An indication of non-thermal phase transition is obtained where the anisotropic scaling behavior (self affinity) of dynamical fluctuation is best revealed (H = 0.8). [ABSTRACT FROM AUTHOR]

This paper presents a fractality analysis of the compound multiplicity (pions + target protons) distribution in 12C–AgBr interactions at 4.5A GeV in terms of moments proposed by Takagi (Phys. Rev. Lett. 72, 32 (1994)) for both emission-angle (θ) and azimuthal-angle (φ) space. The generalized dimensions Dq, q = 1 to 5, have been calculated and compared to other studies. The analysis reveals the multifractal nature of particle production as a common feature of emission of different patterns in high-energy nuclear collisions. PACS Nos.: 25.75–q, 24.60 Ky [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the analysis of jet-like and ring-like events to study the rapidity gap probability of pions produced in 16O–AgBr interactions at 60AGeV. The study reveals the scaling behavior of the void probability for the jet-like events. However for ring-like events, the rapidity gap probability does not obey the scaling law. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

Self-affine multiplicity scaling is investigated in the framework of two-dimensional factorial moment methodology using the concept of the Hurst exponent (H) considering different bins of the phase space. We have investigated the fluctuation pattern of emitted pions in 24Mg-AgBr interactions at 4.5 AGeV and this study reveals that the fluctuation is self-similar in some bins, whereas it is self-affine in other bins, that is, the multiplicity scaling is bin-dependent. [ABSTRACT FROM AUTHOR]

This paper presents evidence of intermittency in target fragmentation in [SUP28]Si-AgBr interactions at 14.5 AGeV in emission angle space and azimuthal angle space separately and also in two-dimensional (cos θ,φ) space. From the intermittency exponent, the anomalous fractal dimension d[SUBq] is calculated and the variation of d[SUBq] with the order q is investigated. The authors also compare the results with those obtained from [SUP16]O-AgBr interactions at 60 AGeV and at 2.1 AGeV and [SUP32]S-AgBr interactions at 200 AGeV to study the energy dependence of intermittent type of uctuations in emission angle and azimuthal angle space separately. Comparing the intermittency exponents in one- and two-dimensions it is further seen that intermittency exponent has a higher value in two-dimensional space. [ABSTRACT FROM AUTHOR]

The possible signature of chaotic behavior of multiparticle production in nucleus–nucleus collision has been investigated with the help of a new parameter, the entropy index μq. This index describes the event-to-event fluctuation of factorial moments which measures the spatial fluctuation of the multiplicity distribution. An analysis of 32S–AgBr interaction data at 200 A GeV reveals a large value for the entropy index signifying chaotic behavior of the multipion production process in ultrarelativistic nuclear interactions. [Copyright &y& Elsevier]

This paper presents an analysis of medium energy target protons emitted in [sup 32]S-AgBr interactions at 200 AGeV and [sup 16]O-AgBr interactions at 60 AGeV in terms of scaled factorial moments up to the fifth order. The study gives evidence of a nonthermal phase transition in the [sup 32]S-AgBr data. The multifractal nature of the particle spectra has also been observed using a new method proposed by F. Takagi. [ABSTRACT FROM AUTHOR]