Non-Gaussian perturbations in hybrid inflation

We consider second order inflationary perturbations in the case of two scalar fields, \σ and the inflaton \φ. We derive an expression for the non-Gaussianity of perturbations and apply the results to hybrid inflation. We isolate the contributions due to \σ and evaluate the resulting terms to show that \σ-induced non-Gaussianities dominate over inflaton-induced non-Gaussianities when m²\σ \ \η H², where \η is the slow-roll parameter. This may provide a useful test of hybrid inflation in forthcoming CMB experiments.