Right-Handed Sneutrinos as Thermal Dark Matter

Abstract

We analyse the abundance of right-handed sneutrinos in the supersymmetric FD-term model of hybrid inflation. As well as providing a natural solution to the μ- and gravitino overabundance problems, the model offers the lightest right-handed sneutrino as a candidate for thermal dark matter. The FD-term model predicts a new quartic coupling of purely right-handed sneutrinos to the Higgs doublets that thermalises the sneutrinos and makes them annihilate sufficiently fast to a level compatible with the current cosmic microwave background data. We discuss this scenario and identify favourable regions of the parameter space within mSUGRA.