Connecting Direct Dark Matter Detection Experiments to Cosmologically Motivated Halo Models

TL;DR

This paper explores how variations in the galactic dark matter velocity distribution, derived from cosmological simulations, can reconcile conflicting results from different direct detection experiments.

Contribution

It introduces a VDF parameter space from cosmological simulations and shows how experimental tensions can be resolved within this framework.

Findings

Contradictory experimental results can be consistent within the VDF parameter space.

Future limits should consider marginalization over VDF parameters.

Highlights the importance of galactic velocity distribution in dark matter detection.

Abstract

Several direct detection experiments, including recently CDMS-II, have reported signals consistent with 5 to 10 GeV dark matter (DM) that appear to be in tension with null results from XENON and LUX experiments; these indicate a careful review of the theoretical basis, including the galactic DM velocity distribution function (VDF). We establish a VDF parameter space from DM-only cosmological simulations and illustrate that seemingly contradictory experimental results can be made consistent within this parameter space. Future experimental limits should be reported after they are marginalized over a range of VDF parameters.