Forward–backward multiplicity correlation in high-energy nucleus–nucleus interactions at a few AGeV/c

Abstract

We have presented a systematic study of two-particle rapidity correlations in terms of investigating the dynamical fluctuation observable σ 2 c in the forwardbackward pseudo-rapidity windows by analyzing the experimental data of 16 O-AgBr interactions at 4.5 AGeV/c, 22 Ne-AgBr interactions at 4.1 AGeV/c, 28 Si-AgBr and 32 S-AgBr interactions at 4.5 AGeV/c. The experimental results have been compared with the results obtained from the analysis of event sample simulated (MC-RAND) by generating random numbers and also with the analysis of events generated by the UrQMD and AMPT model. Our study confirms the presence of strong short-range correlations among the produced particles in the forward and the backward pseudo-rapidity region. The analysis of the simple Monte Carlo-simulated (MC-RAND) events signifies that the observed correlations are not due to mere statistics only; explanation of such correlations can be attributed to the presence of dynamical fluctuations during the production of charged pions. Comparisons of the experimental results with the results obtained from analyzing the UrQMD data sample indicate that the UrQMD model cannot reproduce the experimental findings. The AMPT model also cannot explain the experimental results satisfactorily. Comparisons of our experimental results with the results obtained from the analysis of higher energy emulsion data and with the results of the RHIC data have also been presented.

Event-by-event analysis of maximum pseudo-rapidity gap fluctuation in high-energy nucleus-nucleus collisions

“…Detailed analysis on systematic errors for the same data set has been presented in our earlier publication [48][49]. From our previous papers [48][49], we find that the efficiency of identifying the shower particles contribute to the systematic error of the analysis. We have shown that [48][49] applying the along the track scanning procedure with the help of two independent observers helps us to increase the scanning efficiency to more than 99% and hence to minimize the systematic errors to less than 1%.…”

“…We have shown that [48][49] applying the along the track scanning procedure with the help of two independent observers helps us to increase the scanning efficiency to more than 99% and hence to minimize the systematic errors to less than 1%. It 11 has been mentioned in [48][49] that along the track scanning method gives reliable event samples because of its high detection efficiency. In nuclear emulsion detector tracks of   e e pair origi ati g fro γ -conversion may cause problem in the identification of pions [48][49].…”

“…It 11 has been mentioned in [48][49] that along the track scanning method gives reliable event samples because of its high detection efficiency. In nuclear emulsion detector tracks of   e e pair origi ati g fro γ -conversion may cause problem in the identification of pions [48][49]. These tracks are produced at a distance from the interaction point after travelling through certain radiation lengths.…”

Multifractal Analysis of Charged Particle Multiplicity Distribution in the Framework of Renyi Entropy

“…In order to collect the data used for the present analysis, stacks of NIKFI-BR2 emulsion pellicles of dimension 20cm 10 cm 600 were irradiated by the 16 O, 28 Si and 32 S beam at 4.5 AGeV/c obtained from the Synchrophasatron at the Joint Institute of Nuclear Research (JINR), Dubna, Russia [78][79][80][81]. According to the Powell [82], in nuclear emulsion detector particles emitted and produced from an interaction are classified into four categories, namely the shower particles, the grey particles, the black particles and the projectile fragments.…”

Energy Dependence of Anti-kaon-to-Kaon Ratio in High-energy Collisions --- A Simulated Study

“…To account for the quantum statistics, the hadrons are represented by Gaussian wave packets and effects such as, e.g., Pauli blocking are included in this model. Both UrQMD [29][30][31][32][33][34][35] and DPMJET III [36][37][38] models have been applied successfully to study high-energy collisions.…”