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arXiv · 1508.04773

Accretion of dark matter by stars

Richard Brito·Vitor Cardoso·Hirotada Okawa
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Abstract

Searches for dark matter imprints are one of the most active areas of current research. We focus here on light fields with mass $m_B$, such as axions and axion-like candidates. Using perturbative techniques and full-blown nonlinear Numerical Relativity methods, we show that (i) dark matter can pile up in the center of stars, leading to configurations and geometries oscillating with frequency which is a multiple of f=$2.5 10^{14}$ $m_B c^2$/eV Hz. These configurations are stable throughout most of the parameter space, and arise out of credible mechanisms for dark-matter capture. Stars with bosonic cores may also develop in other theories with effective mass couplings, such as (massless) scalar-tensor theories. We also show that (ii) collapse of the host star to a black hole is avoided by efficient gravitational cooling mechanisms.

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Richard Brito, Vitor Cardoso, Hirotada Okawa. 2015-08-19. Accretion of dark matter by stars. https://doi.org/10.1103/physrevlett.115.111301

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