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arXiv · 1210.0400

Chemical and mechanical instability in warm and dense nuclear matter

A. Lavagno·D. Pigato
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Abstract

We investigate the possible thermodynamic instability in a warm and dense nuclear medium (T<50 MeV and \rho_0<\rho_B< 3\rho_0) where a phase transition from nucleonic matter to resonance-dominated Delta-matter can take place. The analysis is performed by requiring the global conservation of baryon and electric charge numbers in the framework of a relativistic equation of state. Similarly to the liquid-gas phase transition, we show that the nucleon-Delta matter phase transition is characterized by both mechanical instability (fluctuations on the baryon density) and by chemical-diffusive instability (fluctuations on the charge concentration) in asymmetric nuclear matter. We then perform an investigation and a comparative study on the different nature of such instabilities and phase transitions.

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A. Lavagno, D. Pigato. 2012-10-01. Chemical and mechanical instability in warm and dense nuclear matter. https://doi.org/10.1103/physrevc.86.024917

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