Common Signatures of Statistical Coulomb Fragmentation of Highly Excited Nuclei and Phase Transitions in Confined Microcanonical Systems

Abstract

Characteristic signatures of statistical Coulomb fragmentation of highly excited nuclear systems were analyzed. It was found that in some important aspects, they coincide with perceived signatures of phase transitions in confined hypothetical pseudo-microcanonical systems, thus potentially giving rise to a false interpretation of experimental observations in terms of phase transitions. It is demonstrated that the heat capacity as derived based on experimental observations may show domains of faux negative heat capacity for the same fundamental reason a faux negative heat capacity appears in constrained numerical modeling of phase transitions in excited nuclear matter, the reason being an effective truncation of the microcanonical phase space. Similarly, selected experimental data may exhibit bimodality apparently in accordance with the truncated pseudo-microcanonical (but not the true microcanonical) calculations for confined systems.

arXiv comment23 pages, 7 figures

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Cited by in corpus (1)

• Nuclear multifragmentation time-scale and fluctuations of largest fragment size