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Experimental and Theoretical Search for a Phase Transition in Nuclear Fragmentation

A. Chbihi·O. Schapiro·S. Salou·D. H. E. Gross
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Abstract

Phase transitions of small isolated systems are signaled by the shape of the caloric equation of state e^*(T), the relationship between the excitation energy per nucleon e^* and temperature. In this work we compare the experimentally deduced e^*(T) to the theoretical predictions. The experimentally accessible temperature was extracted from evaporation spectra from incomplete fusion reactions leading to residue nuclei. The experimental e^*(T) dependence exhibits the characteristic S-shape at e^* = 2-3 MeV/A. Such behavior is expected for a finite system at a phase transition. The observed dependence agrees with predictions of the MMMC-model, which simulates the total accessible phase-space of fragmentation.

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A. Chbihi, O. Schapiro, S. Salou, D. H. E. Gross. 1999-01-14. Experimental and Theoretical Search for a Phase Transition in Nuclear Fragmentation. https://arxiv.org/abs/nucl-th/9901016

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