Supergravity inspired Vector Curvaton

Understand

It is investigated whether a massive Abelian vector field, whose gauge kinetic function is growing during inflation, can be responsible for the generation of the curvature perturbation in the Universe.

• Particle production is studied and it is shown that the vector field can obtain a scale invariant superhorizon spectrum of perturbations with a reasonable choice of kinetic function.
• After inflation the vector field begins coherent oscillations, during which it corresponds to pressureless isotropic matter.
• When the vector field dominates the Universe its perturbations give rise to the observed curvature perturbation following the curvaton scenario.