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On Statistical Mechanics Developments of Clan Concept in Multiparticle Production

M. Brambilla·A. Giovannini·R. Ugoccioni
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Abstract

Clan concept has been introduced in multiparticle dynamics in order to interpret the wide occurrence of negative binomial (NB) regularity in n-charged particle multiplicity distributions (MDs) in various high energy collisions. The centrality of clan concept led to the attempt to justify its occurrence within a statistical model of clan formation and evolution. In this framework all thermodynamical potentials have been explicitly calculated in terms of NB parameters. Interestingly it was found that NB parameter k corresponds to the one particle canonical partition function. The goal of this paper is to explore a possible temperature and volume dependence of parameter k in various classes of events in high energy hadron-hadron collisions. It is shown that the existence of a phase transition at parton level from the ideal clan gas associated to the semihard component with k>1 to the ideal clan gas of the hard component with k<1 implies a discontinuity in the average number of particles at hadron level.

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M. Brambilla, A. Giovannini, R. Ugoccioni. 2007-12-16. On Statistical Mechanics Developments of Clan Concept in Multiparticle Production. https://doi.org/10.1016/j.physa.2007.10.047

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