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arXiv · 1711.03103

Constraining a Thin Dark Matter Disk with Gaia

Katelin Schutz·Tongyan Lin·Benjamin R. Safdi·Chih-Liang Wu
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Abstract

If a component of the dark matter has dissipative interactions, it could collapse to form a thin dark disk in our Galaxy that is coplanar with the baryonic disk. It has been suggested that dark disks could explain a variety of observed phenomena, including periodic comet impacts. Using the first data release from the $Gaia$ space observatory, we search for a dark disk via its effect on stellar kinematics in the Milky Way. Our new limits disfavor the presence of a thin dark matter disk, and we present updated measurements on the total matter density in the Solar neighborhood.

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Katelin Schutz, Tongyan Lin, Benjamin R. Safdi, Chih-Liang Wu. 2018-08-30. Constraining a Thin Dark Matter Disk with Gaia. https://doi.org/10.1103/physrevlett.121.081101

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