Resolving astrophysical uncertainties in dark matter direct detection

TL;DR

This paper examines how uncertainties in the galactic dark matter velocity distribution affect direct detection experiment interpretations, proposing a framework to compare results without assuming specific halo models.

Contribution

It introduces a method to explicitly incorporate astrophysical uncertainties into dark matter detection data analysis, enabling more consistent comparisons across experiments.

Findings

DAMA, CoGeNT, and CRESST-II results can align with anisotropic velocity distributions.

Constraints from CDMS and XENON remain robust despite astrophysical uncertainties.

The framework allows for a more model-independent interpretation of detection results.

Abstract

We study the impact of the assumed velocity distribution of galactic dark matter particles on the interpretation of results from nuclear recoil detectors. By converting experimental data to variables that make the astrophysical unknowns explicit, different experiments can be compared without implicit assumptions concerning the dark matter halo. We extend this framework to include the annual modulation signal, as well as multiple target elements. Recent results from DAMA, CoGeNT and CRESST-II can be brought into agreement if the velocity distribution is very anisotropic and thus allows a large modulation fraction. However constraints from CDMS and XENON cannot be evaded by appealing to such astrophysical uncertainties alone.