Emission Angle Space Research Articles

Two and three particle correlations in target fragmentation at relativistic nucleus–nucleus collisions

Two and three particle short-range correlations among the target evaporated fragments as well as the target recoil protons produced in 12 A GeV 4He-, 3.7 A GeV 16O-, 60 A GeV 16O-, 1.7 A GeV 84Kr- and 10.7 A GeV 197Au-AgBr interactions are investigated in emission angle space and azimuthal angle space, respectively. The experimental data exhibit two and three particle correlations among the target fragments in emission angle space, which indicate the occurrence of so-called side splash phenomena and disfavor the evaporation model. In azimuthal angle space the data exhibit strong two particle correlations for both the target evaporated fragments and target recoil protons, and three particle correlations only for target recoil protons.

Genuine two particle correlations of target fragments in nuclear interactions

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.

LÉVY INDEX AND MULTIFRACTAL CHARACTERISTICS OF RING-LIKE AND JET-LIKE EVENTS IN HIGH ENERGY NUCLEAR COLLISIONS

We perform a Lévy index analysis of relativistic shower particles produced in the interactions of 32 S 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 32 S - 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.

Evidence of intermittent fluctuation of target residue in 84Kr–AgBr interactions at 1.7 A GeV

Intermittency and fractal behavior have been studied for emission spectra of target associated fragments from 84Kr–AgBr interactions at 1.7 A GeV in emission angle space and azimuthal angle space separately. Intermittent behavior is observed for both spaces. From the intermittency exponent, the anomalous fractal dimension d q is calculated and the variation of d q with the order q is investigated. It is found that the anomalous dimensions increase with the order of moments q thereby indicating the association of multifractility with production mechanism of target associated fragments.

Evidence of intermittent fluctuation of target fragments in 84 Kr–AgBr interactions at 1.7 A GeV

Intermittency and fractal behaviour have been studied of emission spectra of target associated fragments from 84Kr–AgBr interactions at 1.7A GeV in emission angle space and azimuthal angle space separately. The intermittent behaviour is observed in the two spaces separately. From the intermittency exponent, the anomalous fractal dimension dq is calculated and the variation of dq with the order q is investigated. It is found that the anomalous dimensions are found to increase with the order of moments q, thereby indicating the relation of multifractality to production mechanism of target associated fragments.

Evidence of strong two-particle and three-particle dynamical correlation in compound multiplicity distribution in nucleus–nucleus interactions at 4.5 AGeV

This paper reports an investigation of two- and three-particle dynamical correlation in multiparticle production processes in terms of compound multiplicity (proton and pion) distributions. The data have been taken from 24Mg–AgBr and 12C–AgBr interactions at 4.5 AGeV. The experimental results are compared with those of Monte Carlo simulated events, assuming an independent emission of the compound multiplicity. The data exhibit strong two- and three-particle correlation in both forward and backward hemispheres in emission angle space for both data sets. PACS Nos.: 25.75–q, 24.60 Ky

Observation of Void Probability Scaling of Proton Emission in High Energy Nucleus–Nucleus Collisions

In this paper the study of gap probability of protons has been carried out with 28 Si–AgBr interaction at 14.5 A GeV in emission angle space. The study reveals the scaling behaviour of the void probability which hints towards the outer space–inner space connection. This study also confirms the validity of the linked pair approximation for the N-particle cumulant correlation functions in case of protons.

Evidence of Intermittent Type Fluctuation of Target Residue in Relativistic Nuclear Collisions at a Few Gev/n

This paper presents evidence of intermittency in target fragmentation in 28Si-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 dq is calculated and the variation of dq with the order q is investigated. The authors also compare the results with those obtained from 16O-AgBr interactions at 60 AGeV and at 2.1 AGeV and 32S-AgBr interactions at 200 AGeV to study the energy dependence of intermittent type of fluctuations 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.

Strong Signal of Dynamical Long-Range Correlation among Target Fragments in Relativistic and Ultra-Relativistic Nuclear Interactions

This paper reports an investigation on the two-particle long-range angular correlation among the target fragments produced in 28Si−AgBr interactions at 14.5 AGeV, 16O−AgBr interactions at 60 AGeV and 32S−AgBr interactions at 200 AGeV. The experimental data have been compared with Monte Carlo simulated events to extract dynamical correlation. The data exhibit two-particle long-range correlation in emission angle space at all energies.