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arXiv · 2211.10141

Negative heat capacity for hot nuclei: confirmation with formulation from the microcanonical ensemble

B. Borderie·S. Piantelli·J. D. Frankland·N. Le Neindre
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Abstract

By using freeze-out properties of multifragmenting hot nuclei produced in quasifusion central $^{129}$Xe+$^{nat}$Sn collisions at different beam energies (32, 39, 45 and 50 AMeV) which were estimated by means of a simulation based on experimental data collected by the $4\pi$ INDRA multidetector, heat capacity in the thermal excitation energy range 4 - 12.5 AMeV was calculated from total kinetic energies and multiplicities at freeze-out. The microcanonical formulation was employed. Negative heat capacity which indicates a first order phase transition for finite systems is observed and confirms previous results using a different method.

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B. Borderie, S. Piantelli, J. D. Frankland, N. Le Neindre. 2022-11-18. Negative heat capacity for hot nuclei: confirmation with formulation from the microcanonical ensemble. https://doi.org/10.1393/ncc%2Fi2022-22048-1

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