Rapidity dependence of multiplicity fluctuations and correlations in high-energy nucleus–nucleus interactions

Abstract

The multiplicity fluctuations of the produced pions were studied using scaled variance method in 16 O-AgBr interactions at 2.1 AGeV, 24 Mg-AgBr interactions at 4.5 AGeV, 12 CAgBr interactions at 4.5 AGeV, 16 O-AgBr interactions at 60 AGeV and 32 S-AgBr interactions at 200 AGeV at two different binning conditions. In the first binning condition, the rapidity interval was varied in steps of one centring about the central rapidity until it reached 14. In the second case, the rapidity interval was increased in steps of 1.6 up to 14.4. Multiplicity distributions and their scaled variances were presented as a function of the dependence on the rapidity width for both the binning conditions. Multiplicity fluctuations were found to increase with the increase of rapidity interval and later found to saturate at larger rapidity window for all the interactions and in both the binning conditions. Multiplicity fluctuations were found to increase with the energy of the projectile beam. The values of the scaled variances were found to be greater than one in all the cases in both the binning conditions indicating the presence of correlation during the multiparticle production process in high-energy nucleus-nucleus interactions. Experimental results were compared with the results obtained from the Monte Carlo simulated events for all the interactions. The Monte Carlo simulated data showed very small values of scaled variance suggesting very small fluctuations for the simulated events. Experimental results obtained from 16 O-AgBr interactions at 60 AGeV and 32 SAgBr interactions at 200 AGeV were compared with the events generated by Lund Monte Carlo code (FRITIOF model). FRITIOF model failed to explain the multiplicity fluctuations of pions emitted from 16 O-AgBr interactions at 60 AGeV for both the binning conditions. However, the experimental data agreed well with the FRITIOF model for 32 S-AgBr interactions at 200 AGeV.

Pion Fluctuation in High-energy Collisions --- A Chaos-based Quantitative Estimation with Visibility Graph Technique

“…The details of the events are also elaborated in our earlier works [39,7,40,41,42,43,8]. As per the terminology of nuclear emulsion [?…”

Sensitivity of Multiplicity Fluctuations to Rapidity in High-Energy Nucleus-Nucleus Interactions

“…where Var( ) = ∑︀ ( − ⟨ ⟩) 2 ( ) and (⟨ ⟩ = = ∑︀ ( ) are the variance and mean of the multiplicity distribution. It has been suggested [27][28][29] that an estimate of the scaled variance would be a direct measure of multiplicity fluctuations. The main idea behind these types of studies is that the multiplicity fluctuations are a reflection of particle correlations amongst the particles produced in heavy ion collisions.…”

Study of multiplicity correlations in nucleus–nucleus interactions at high energy

“…29,30 Dong-Hai et al 31 have conducted an analysis of the compound multiplicity in 16 O-emulsion interactions at 4.5A GeV/c. Mohery and Arafa 23 have presented some characteristics of the compound multiplicity in high-energy nucleus-nucleus interactions.…”

“…Mohery and Arafa 23 have presented some characteristics of the compound multiplicity in high-energy nucleus-nucleus interactions. Recently, the characteristics of the compound multiplicity in 84 Kr with various light and heavy targets at 1 GeV per nucleon have been investigated by Chouhan et al 27 In addition, recently several authors [30][31][32][33][34][35][36][37][38] have investigated some characteristics of the multiplicity correlations. Ghosh et al 30 have studied the rapidity dependence of the multiplicity fluctuations and correlations in high-energy nucleusnucleus interactions.…”