Charge Fluctuations in pp and AA Collisions at RHIC and LHC Energies

Shakeel Ahmad, M. Zafar, M. Irfan, A. Ahmad

Department of Applied Physics, Aligarh Muslim University, Aligarh, India.
Department of Physics, Aligarh Muslim University, Aligarh, India.

DOI: 10.4236/wjnst.2012.24031                

Abstract

Various measures of event-by-event net charge and charge ratio fluctuations in pp and AA collisions at RHIC and LHC energies are studied using the different Monte Carlo generators: URQMD, HIJING and HIJING/ and the results are compared with the predictions for the independent emission, hadron gas and QGP phase. Values of the D-measures are observed to exhibit significant energy dependence for both pp and AA data. Furthermore, there is essentially no significant difference in the values of the D-measures predicted by the various Monte Carlo codes used in the present study. A slight centrality dependence of the D-measures in terms of net charge fluctuations is observed in the case of Au-Au data at 200A GeV/c. These findings, thus, suggest that a difference in the D-measures for pp and AA collisions either the re-scattering effect plays a predominant role or there might be some new physics present in these collisions.

Keywords

Hadron-Hadron Collisions; Heavy-Ion Collisions; Charge Fluctuations

Conflicts of Interest

The authors declare no conflicts of interest.

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