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arXiv · 2412.13568

Neutron stars with a dark-energy core from the Chaplygin gas

Juan M. Z. Pretel·Mariana Dutra·Sergio B. Duarte
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Abstract

We analyze the effect of a Chaplygin dark fluid (CDF) core on neutron stars (NSs). To address this study, we focus on the relativistic structure of stellar configurations composed by a dark-energy core, described by a Chaplygin-like equation of state (EoS), and an ordinary-matter crust which is described by a polytropic EoS. We examine the impact of the rate of energy densities at the discontinuous surface, defined as $\alpha= \rho_{\rm dis}^-/\rho_{\rm dis}^+$, on the radius, total gravitational mass, oscillation spectrum and tidal deformability. Furthermore, we compare our theoretical predictions with several observational mass-radius measurements and tidal deformability constraints. These comparisons together with the radial stability analysis show that the existence of NSs with a dark-energy core is possible.

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Juan M. Z. Pretel, Mariana Dutra, Sergio B. Duarte. 2024-12-18. Neutron stars with a dark-energy core from the Chaplygin gas. https://arxiv.org/abs/2412.13568

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