$\alpha$ particles and the pasta phase

Abstract

The effects of the $\alpha$ particles in nuclear matter at low densities are investigated within three different parametrizations of relativistic models at finite temperature. Both homogeneous and inhomogeneous matter (pasta phase) are described for neutral nuclear matter with fixed proton fractions and stellar matter subject to $\beta$-equilibrium and trapped neutrinos. In homogeneous matter, $\alpha$ particles are only present at densities below 0.02 fm${}^{-3}$ and their presence decreases with the increase of the temperature and, for a fixed temperature, the $\alpha$ particle fraction decreases for smaller proton fractions. A repulsive interaction is important to mimic the dissolution of the clusters in homogeneous matter. The effects of the $\alpha$ particles on the pasta structure is very small except close to the critical temperatures and / or proton fractions when it may still predict a pasta phase while no pasta phase would occur in the absence of light clusters. It is shown that for densities above 0.01 fm${}^{-3}$ the $\alpha$ particle fraction in the pasta phase is much larger than the $\alpha$ particle fraction in homogeneous matter.

15 pages, 9 figures

References in corpus (8)

• Formation of Nuclear "Pasta" in Supernovae
• Locating the inner edge of neutron star crust using terrestrial nuclear laboratory data
• The pasta phase within density dependent hadronic models
• Dirac-Brueckner-Hartree-Fock calculations for isospin asymmetric nuclear matter based on improved approximation schemes
• Nuclear matter in the crust of neutron stars derived from realistic NN interactions
• Cluster formation in compact stars: relativistic versus Skyrme models
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• Dynamical instabilities of warm $np{e}^{-}$ matter: the $\delta$ meson effects

Cited by in corpus (26)

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• Description of light clusters in relativistic nuclear models
• The importance of the mixed phase in hybrid stars built with the Nambu-Jona-Lasinio model
• The pasta phase and its consequences on neutrino opacities
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• Pasta phases within the QMC model
• Hyperons in the pasta phase
• Pasta fluctuations in symmetric matter at finite temperature
• Latent heat of nuclear matter
• Warm unstable asymmetric nuclear matter: critical properties and the density dependence of the symmetry energy
• Light clusters in warm stellar matter: calibrating the cluster couplings
• Fluctuations in the pasta phase
• Strong magnetic fields: neutron stars with an extended inner crust
• Towards a quantal dynamical simulation of the neutron-star crust
• Influence of the tetraneutron on the EoS under core-collapse supernovae and heavy-ion collisions conditions
• Unified treatment for in-medium light and heavy clusters with RMF models
• Fully antisymmetrised dynamics for bulk fermion systems
• Light hyperclusters and hyperons in low-density hot stellar matter