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arXiv · 0908.2259

Dynamical instabilities of warm $npe^-$ matter: the $δ$ meson effects

Helena Pais·Alexandre Santos·Constança Providência
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Abstract

The effects of $δ$ mesons on the dynamical instabilities of cold and warm nuclear and stellar matter at subsaturation densities are studied in the framework of relativistic mean-field hadron models (NL3, NL$ρ$ and NL$ρδ$) with the inclusion of the electromagnetic field. The distillation effect and the spinodals for all the models considered are discussed. The crust-core transition density and pressure are obtained as a function of temperature for $β$-equilibrium matter with and without neutrino trapping. An estimation of the size of the clusters formed in the non-homogeneous phase is made. It is shown that cluster sizes increase with temperature. The effects of the $δ$-meson on the instability region are larger for low temperatures, very asymmetric matter and densities close to the spinodal surface. It increases the distillation effect above $\sim 0.4ρ_0$ and has the opposite effect below that density.

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Helena Pais, Alexandre Santos, Constança Providência. 2009-08-16. Dynamical instabilities of warm $npe^-$ matter: the $δ$ meson effects. https://doi.org/10.1103/physrevc.80.045808

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