[Submitted on 20 Apr 2026] (cross-list from astro-ph.HE)
Equation of State for warm Neutron Star outer crusts
David Barba-González · Conrado Albertus · M. Ángeles Pérez-García
We describe the equation of state (EoS) of a warm ion plasma as obtained by performing microscopic many-body simulations using Molecular Dynamics computational techniques. Using the cold one-component plasma (OCP) composition in the Neutron Star (NS) outer crust assumed in Murarka et al. (2022) with a representative heavy nucleus for each density, we refine previous calculations. We include electron screening and modeling of ions as finite-size Gaussian distributions in the interaction potential, together with an efficient Ewald energy summation procedure. From this, the EoS relation is obtained as a function of baryonic density and temperature in the NS outer crust under conditions , MeV. In order to improve the usability of our results we provide tabulated data values along with a neural network parametrization available in the Zenodo repository, see https://zenodo.org/records/15348712. We find that even at moderate temperatures, thermal effects of ions are key in the higher density region closer to the inner crust, when described using a thermal effective parametrization based on the thermal adiabatic index . We compare our results with other EoS in the literature performing a critical discussion.
- Comments:
- 11 pages, 5 figures, 1 table
- Subjects:
- High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR); Nuclear Theory (nucl-th); Plasma Physics (physics.plasm-ph)
- arXiv:
- 2604.18136 [pdf]