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Quasi-gaussian fixed points and factorial cumulants in nuclear multifragmentation

D. Lacroix·R. Peschanski
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Abstract

We re-analyze the conditions for the phenomenon of intermittency (self-similar fluctuations) to occur in models of multifragmentation. Analyzing two different mechanisms, the bond-percolation and the ERW (Elattari, Richert and Wagner) statistical fragmentation models, we point out a common quasi-gaussian shape of the total multiplicity distribution in the critical range. The fixed-point property is also observed for the multiplicity of the second bin. Fluctuations are studied using scaled factorial cumulants instead of scaled factorial moments. The second-order cumulant displays the intermittency signal while higher order cumulants are equal to zero, revealing a large information redundancy in scaled factorial moments. A practical criterion is proposed to identify the gaussian feature of light-fragment production, distinguishing between a self-similarity mechanism (ERW) and the superposition of independent sources (percolation).

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D. Lacroix, R. Peschanski. 1996-06-11. Quasi-gaussian fixed points and factorial cumulants in nuclear multifragmentation. https://doi.org/10.1016/s0375-9474(97)00476-4

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