Measuring the local dark matter density in the laboratory

Despite strong evidence for the existence of large amounts of dark matter (DM) in our Universe, there is no direct indication of its presence in our own solar system. All estimates of the local DM density rely on extrapolating results on much larger scales. We demonstrate for the first time the possibility of simultaneously measuring the local DM density and interaction cross section with a direct detection experiment. It relies on the assumption that incoming DM particles frequently scatter on terrestrial nuclei prior to detection, inducing an additional time-dependence of the signal. We show that for sub-GeV DM, with a large spin-independent DM-proton cross section, future direct detection experiments should be able to reconstruct the local DM density with smaller than 50% uncertainty.

Automated summary

Despite strong evidence for the existence of large amounts of dark matter in the Universe, there is no direct indication of its presence in our solar system. A new study demonstrates the possibility of measuring the local dark matter density and interaction cross section through direct detection experiments. This study suggests that future experiments may be able to reconstruct the local dark matter density with less than 50% uncertainty for sub-GeV dark matter with a large spin-independent DM-proton cross section.