Theoretical directional and modulated rates for direct supersymmetric dark matter detection

Exotic dark matter together with vacuum energy (cosmological constant) seem to dominate in a flat universe. Thus direct dark matter detection is central to particle physics and cosmology. Supersymmetry provides a natural dark matter candidate, the lightest supersymmetric particle. It is possible to obtain detectable rates, but realistically they are expected to be much lower than the present experimental goals. So one should exploit two characteristic signatures of the reaction: namely, the modulation effect and the correlation with the Sun's motion in directional experiments. In standard nondirectional experiments the modulation is small, less than 2%. In the case of directional experiments, the main subject of this paper, we find two novel features, which are essentially independent of the supersymmetry model employed; namely, (1) the forward-backward asymmetry, with respect to the Sun's direction of motion, is very large and (2) the modulation observed in a plane perpendicular to the Sun's motion can be higher than 20% and is direction dependent.