Dirac Sneutrino as a Light Dark Matter

We show the property of light right-handed Dirac sneutrino dark matter candidate. While the light Dirac sneutrino is stringently constrained by the invisible decay width of the Z boson, its scattering cross section with nucleon through the Z boson exchange can be a large enough to account for possible signals observed at direct dark matter searches, such as CDMS II(Si) or CoGeNT. Althrough the sneutrino scatters with mostly neutrons, a small part of the signal region for CDMS II(Si) events remains outside the region excluded by XENON100(2012).