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The chemical equilibration volume: measuring the degree of thermalization

A. Majumder·V. Koch
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Abstract

We address the issue of the degree of equilibrium achieved in a high energy heavy-ion collision. Specifically, we explore the consequences of incomplete strangeness chemical equilibrium. This is achieved over a volume V of the order of the strangeness correlation length and is assumed to be smaller than the freeze-out volume. Probability distributions of strange hadrons emanating from the system are computed for varying sizes of V and simple experimental observables based on these are proposed. Measurements of such observables may be used to estimate V and as a result the degree of strangeness chemical equilibration achieved. This sets a lower bound on the degree of kinetic equilibrium. We also point out that a determination of two-body correlations or second moments of the distributions are not sufficient for this estimation.

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A. Majumder, V. Koch. 2003-05-16. The chemical equilibration volume: measuring the degree of thermalization. https://doi.org/10.1103/physrevc.68.044903

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