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arXiv · 2312.13836

Effect of the equation of state for dilute neutron matter on the composition of the inner crust of neutron stars

Sunny Kumar Gupta·Michael Urban
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Abstract

The composition of the inner crust of neutron stars is usually studied using phenomenological interactions such as Skyrme energy-density functionals. But most of these functionals do not agree well with ab-initio calculations of very dilute neutron matter. In this work, we study the inner crust of neutron stars in the model of phase coexistence of dense neutron-rich nuclear clusters and dilute neutron gas, and we investigate how employing a realistic microscopic equation of state to the neutron gas alters the composition. Our results indicate that with a functional that reproduces the correct equation of state of neutron matter at moderate densities, one can obtain a good description of the crust even if the functional does not have the correct behavior at extremely low density.

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Sunny Kumar Gupta, Michael Urban. 2023-12-21. Effect of the equation of state for dilute neutron matter on the composition of the inner crust of neutron stars. https://doi.org/10.1103/physrevc.109.045806

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