Laser Interferometers as Dark Matter Detectors
While the global cosmological and local galactic abundance of dark matter is well established, its identity, physical size, and composition remain a mystery. In this paper, we analyze an important question of dark matter detectability through its gravitational interaction, using current and next generation gravitational-wave observatories to look for macroscopic (kilogram-scale or larger) objects. Keeping the size of the dark matter objects to be smaller than the physical dimensions of the detectors, and keeping their mass as a free parameter, we derive the expected event rates. For favorable choice of mass, we find that dark matter interactions could be detected in space-based detectors such as LISA at a rate of one per ten years. We then assume the existence of an additional Yukawa force between dark matter and regular matter. By choosing the range of the force to be comparable to the size of the detectors, we derive the levels of sensitivity to such a new force, which exceeds the sensitivity of other probes in a wide range of parameters. For sufficiently large Yukawa coupling strength, the rate of dark matter events can then exceed 10 per year for both ground- and space-based detectors. Thus, gravitational-wave observatories can make an important contribution to a global effort of searching for nongravitational interactions of dark matter.
© 2018 American Physical Society. Received 2 May 2016; published 23 October 2018. The work of M. P. is supported in part by NSERC, Canada, and research at the Perimeter Institute is supported in part by the Government of Canada through NSERC and by the Province of Ontario through MEDT. E. D. H., V. V. F., and R. X. A. are supported in part by the NSF under Award No. PHY-0757058. The authors would like to thank Thomas Callister for useful discussions during the early part of this work.
Submitted - 1605.01103v1.pdf
Published - PhysRevD.98.083019.pdf