Event-by-Event pseudorapidity fluctuation analysis: An outlook to multiplicity and phase space dependence

A detailed study of Event-by-Event pseudorapidity fluctuation of the pions produced in O-16-AgBr interactions at 60 A GeV and S-32-AgBr interactions at 200 A GeV has been carried out in terms of phi, a variable defined as a measure of fluctuation. Non-zero phi values indicate the presence of strong correlation among the pions for both interactions. Multiplicity and rapidity dependence of the Event-by-Event pseudorapidity fluctuation has been investigated. A decrease of phi with average multiplicity and increase of the same variable with pseudorapidity width are observed. Decrease of phi with average multiplicity is concluded as the particle emission by several independent sources occurs for higher-multiplicity events. The increase in phi values with pseudorapidity width, taken around central rapidity, might hint towards the presence of long-range correlation and its dominance over short range one. We have compared our experimental results with Monte Carlo simulation generated assuming independent particle emission. Comparison shows that the source of correlation and fluctuation is the dynamics of the pion production process. We have also compared our results with events generated by FRITIOF code. Such events also show the presence of fluctuation and correlation; however they fail to replicate the experimental findings.