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arXiv · 1111.1787

Dark-Matter Admixed Neutron Stars

S. -C. Leung·M. -C. Chu·L. -M. Lin
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Abstract

We study the hydrostatic equilibrium configuration of an admixture of degenerate dark matter and normal nuclear matter by using a general relativistic two-fluid formalism. We consider non- self-annihilating dark matter particles of mass ~ 1 GeV. The mass-radius relations and moments of inertia of these dark-matter admixed neutron stars are investigated and the stability of these stars is demonstrated by performing a radial perturbation analysis. We find a new class of compact stars which consists of a small normal matter core with radius of a few km embedded in a ten-kilometer- sized dark matter halo. These stellar objects may be observed as extraordinarily small neutron stars that are incompatible with realistic nuclear matter models.

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S. -C. Leung, M. -C. Chu, L. -M. Lin. 2011-11-08. Dark-Matter Admixed Neutron Stars. https://doi.org/10.1103/physrevd.84.107301

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