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arXiv · 1704.01668

Dynamics of dwarf galaxies disfavor stellar-mass black hole dark matter

Savvas M. Koushiappas·Abraham Loeb
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Abstract

We study the effects of black hole dark matter on the dynamical evolution of stars in dwarf galaxies. We find that mass segregation leads to a depletion of stars in the center of dwarf galaxies and the appearance of a ring in the projected stellar surface density profile. Using Segue 1 as an example we show that current observations of the projected surface stellar density rule out at the 99.9% confidence level the possibility that more than 6% of the dark matter is composed of black holes with a mass of few tens of solar masses.

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Savvas M. Koushiappas, Abraham Loeb. 2017-08-06. Dynamics of dwarf galaxies disfavor stellar-mass black hole dark matter. https://doi.org/10.1103/physrevlett.119.041102

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