How compact stars challenge our view about dark matter

Grigoris Panotopoulos

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arXiv · 1910.02279

How compact stars challenge our view about dark matter

Grigoris Panotopoulos

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Abstract

It is by now well established that non-relativistic matter in the Universe is dominated by dark matter, the origin and nature of which still remains a mystery. Although the collisionless dark matter paradigm works very well at large distances, a few puzzles at galactic scales arise. These problems may be tackled assuming a self-interacting dark matter. If dark matter is accumulated inside a star it will modify its evolution and its properties, such as mass-to-radius profiles and frequency oscillation modes. Asteroseismology is a relatively new, powerful tool that allows us to constrain dark matter models, offering us complementary bounds to the results coming from other means, such as collider or direct searches. I will present here the main results we have obtained assuming that the dark matter particle is a boson, which inside a star is modelled as a Bose-Einstein condensate with a polytropic equation-of-state. We have computed i) the radial and non-radial oscillation modes of light clumps of dark matter made of ultra light repulsive scalar fields, and ii) the mass-to-radius profiles as well the frequencies of radial modes of admixed dark matter strange quark stars.

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Grigoris Panotopoulos. 2019-10-05. How compact stars challenge our view about dark matter. https://arxiv.org/abs/1910.02279

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