We consider the possibility that a right-handed sneutrino can serve as the source of energy density perturbations leading to structure formation in cosmology. The cosmological evolution of a coherently oscillating condensate of right-handed sneutrinos is studied for the case where reheating after inflation is due to perturbative inflaton decays. For the case of Dirac neutrinos, it is shown that some suppression of Planck scalesuppressed corrections to the right-handed neutrino superpotential is necessary in order to have sufficiently late decay of the right-handed sneutrinos. cH2 corrections to the sneutrino mass squared term must also be suppressed during inflation (ucu&0.1), in which case, depending on the magnitude of ucu during inflation, a significantly blue ~if c.0) or red ~if c,0) perturbation spectrum is possible. R parity must also be broken in order to ensure that the Universe is not overclosed by the lightest supersymmetric particles from the late decay ~at temperatures 1210 MeV) of the right-handed sneutrino condensate. The resulting expansion rate during inflation can be significantly smaller than in conventional supersymmetric inflation models ~as low as 106 GeV is possible!. For the case of Majorana neutrinos, a more severe suppression of Planck-suppressed superpotential corrections is required. In addition, the Majorana sneutrino condensate is likely to be thermalized before it can dominate the energy density, which would exclude the Majorana right-handed sneutrino as a curvaton.
One of the first papers to explore the curvaton scenario in supersymmetric particle theories. The first paper to identify the right-handed sneutrino as a natural curvaton candidate. It has motivated a wave of research activity on the connections between neutrino physics and SUSY cosmology. 39 citations (SPIRES). RAE_import_type : Journal article RAE_uoa_type : Physics © 2003 The American Physical Society