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arXiv · 0708.3197

From Microscales to Macroscales in 3D: Selfconsistent Equation of State for Supernova and Neutron Star Models

W. G. Newton·J. R. Stone·A. Mezzacappa
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Abstract

First results from a fully self-consistent, temperature-dependent equation of state that spans the whole density range of neutron stars and supernova cores are presented. The equation of state (EoS) is calculated using a mean-field Hartree-Fock method in three dimensions (3D). The nuclear interaction is represented by the phenomenological Skyrme model in this work, but the EoS can be obtained in our framework for any suitable form of the nucleon-nucleon effective interaction. The scheme we employ naturally allows effects such as (i) neutron drip, which results in an external neutron gas, (ii) the variety of exotic nuclear shapes expected for extremely neutron heavy nuclei, and (iii) the subsequent dissolution of these nuclei into nuclear matter. In this way, the equation of state is calculated across phase transitions without recourse to interpolation techniques between density regimes described by different physical models. EoS tables are calculated in the wide range of densities, temperature and proton/neutron ratios on the ORNL NCCS XT3, using up to 2000 processors simultaneously.

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W. G. Newton, J. R. Stone, A. Mezzacappa. 2007-08-23. From Microscales to Macroscales in 3D: Selfconsistent Equation of State for Supernova and Neutron Star Models. https://doi.org/10.1088/1742-6596/46/1/056

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