Dark Matter Clusters and Time Correlations in Direct Detection Experiments

Understand

Assuming that dark matter (DM) efficiently clusters on various scales we analyse the possible impact on direct DM searches.

• For certain sizes and densities of DM clusters, mutual detector-cluster encounters may occur only once a year or every several years leading to the apparent failure of individual experiments searching for DM to discover it.
• If, however, encounters with Earth size and up to $10^4$ times bigger clusters occur about once a year, then finding time correlations between events in different underground detectors can lead to DM discovery.