Mutual information and forward-backward correlations in multihadron production.

Abstract

Correlations between hadrons produced in the forward and backward hemispheres with respect to the collision axis have been analyzed using the relative mutual information ${I}_{r}$. This simple example provides a model-independent information-theoretical measure of correlations capable of generalization to any order. Evaluation of the F/B mutual information in the NA22 experiment gives ${I}_{r}$=0.02 (0.003) for a rapidity window of 2 for ``all-charge'' (``negative-only'') distributions. For the UA5 experiment at the CERN Collider we obtain the larger value of 0.1 for the pseudorapidity window of 4.