Gravitational Focusing of Low-Velocity Dark Matter on the Earth's Surface

Yoshiaki Sofue

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arXiv · 2005.08252

Gravitational Focusing of Low-Velocity Dark Matter on the Earth's Surface

Yoshiaki Sofue

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Abstract

We show that the Earth acts as a high-efficiency gravitational collector of low-velocity flow of dark matter (DM). The focal point appears on the Earth's surface, when the DM flow speed is about 17 km/s with respect to the geo-center. We discuss diurnal modulation of the local DM density influenced by the Earth's gravity. We also touch upon similar effects on galactic and solar system objects.

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Yoshiaki Sofue. 2020-05-17. Gravitational Focusing of Low-Velocity Dark Matter on the Earth's Surface. https://arxiv.org/abs/2005.08252

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