Model Independent Bounds in Direct Dark Matter Detection

The nature of Dark Matter (DM) is one of the most exciting open questions at the interface between cosmology and particle physics. Since several decades, we have a compelling evidence of unseen mass at different scales. Nevertheless, a non gravitational manifestation of DM is yet to be identified. Direct, indirect and collider searches may shed light on the nature of DM. Hence, a model independent study of its phenomenology is crucial. For a review see, e.g., [1]. Direct detection for DM aim at detecting the feeble kick to an atomic nucleus in underground detectors. DM direct searches experiments are achieving unprecedented sensitivity to DM detection. Indeed, in addition to the long standing DAMA results [2], nowadays there are other three experiments (CoGeNT [3,4], CRESST-II [5] and CDMS-II-Si [6]) with data that may have the right properties to be potentially ascribed to a DM interaction. DAMA [2] and CoGeNT [4] observe an annual modulation in their counting rates, while CRESST-II [5] and CDMS-II-Si [6] report an excess of events above their estimated backgrounds. However, we are far from a definitive and clear discovery because other experiments do not observe any significant excess above their expected backgrounds. The most stringent bounds for the spin-independent interactions are set by LUX [7], XENON100 [8], CDMS-II-Ge [9] and CDMSlite [10], while SIMPLE [11], PICASSO [12] and COUPP [13] setting relevant limits for the DM-p spin-dependent interactions. Nevertheless, when interpreting the different experimental data, one has always to bear well in mind at least two main caveats. The first is that the fine experimental details must be treated with great care. The second caveat is instead associated with the