The Unbearable Lightness of Being: CDMS versus XENON

Abstract

The CDMS-II collaboration has reported 3 events in a Si detector, which are consistent with being nuclear recoils due to scattering of light dark matter particles. We discuss the tension between this result and upper bounds from the XENON10 and XENON100 experiments and under what conditions this tension can be ameliorated. A particular focus will be on experimental uncertainties (for example concerning the ionisation yield Qy) and uncertainties related to the dark matter velocity distribution. Finally, we consider various particle physics modifications of the interactions between dark matter and quarks which can bring XENON10/100 and CDMS-II into better agreement.