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arXiv · 2609.17850

Tidal Properties of White Dwarfs Admixed with Fermionic Dark Matter

G. A. Carvalho·J. D. V. Arbañil·I. A. Lacerda·J. G. Coelho
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Abstract

This study investigates the impact of fermionic dark matter (DM) on the structural and tidal properties of white dwarfs (WDs). Using a two-fluid general relativistic framework, we model stars with fixed DM mass fractions (${\rm MF}=M_{\rm DM}/M_{\rm NM} $), ranging from 0\% to 8\%, with zero representing the no DM scenario. Our results indicate that DM accumulation leads to a significant compactification of the star, reflected in increased surface gravity and compactness. Furthermore, we calculate the second-order tidal Love number $k_2$ and the dimensionless tidal deformability $Λ$. For some total mass range, we find that the presence of DM significantly reduces $Λ$, suggesting that DM-admixed WDs (DMWDs) are less susceptible to tidal deformations. These structural shifts alter the gravitational wave signatures in binary systems, potentially providing a new window for DM detection with future instruments like LISA.

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G. A. Carvalho, J. D. V. Arbañil, I. A. Lacerda, J. G. Coelho. 2026-09-15. Tidal Properties of White Dwarfs Admixed with Fermionic Dark Matter. https://arxiv.org/abs/2609.17850

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