Direct detection data and possible hints for low-mass WIMPs

Abstract

Possible hints for WIMP dark matter with mass around 10 GeV coming from the DAMA, CoGeNT, and maybe also CRESST experiments are presented, and confronted with constraints from CDMS and XENON data. Focusing on spin-independent (SI) WIMP--nucleus interactions, I elaborate on the difficulties to make the hints consistent with each other and to evade the constraints, mentioning energy scale uncertainties, quenching and light-yield factors, as well as uncertainties on halo properties. In the present situation it seems hard to reconcile all data within the SI framework, which suggests that if the experimental anomalies were indeed due to dark matter a more exotic mechanism (to be identified) had to be at work.