ABSTRACT:

If dark matter stems from the background of a very light gauge boson, this gauge boson could exert forces on test masses in gravitational wave detectors, resulting in displacements with a characteristic frequency set by the gauge boson mass. We outline a novel search strategy for such dark matter, assuming the dark photon is the gauge boson of U(1)_B or U(1)_{B-L}. We show that both ground-based and future space-based gravitational wave detectors have the capability to make a 5-sigma discovery in unexplored parameter regimes. Furthermore, we use the publicly available data from LIGO’s first observing run, O1, to perform the first such dark photon dark matter search. We find that, if a dark photon is the gauge boson of U(1)_B, LIGO-O1 data has already provided a sensitivity better, in a small mass band, than achieved by prior experiments.