Non-minimal B−L inflation with observable gravity waves

We consider non-minimal λϕ4 inflation in a gauged non-supersymmetric U(1)B−L model containing the gravitational coupling ξRΦ†Φ, where R denotes the Ricci scalar and the standard model singlet inflaton field Φ spontaneously breaks the U(1)B−L symmetry. Including radiative corrections, the predictions 0.956≲ns≲0.984 and 0.007≲r≲0.1 for the scalar spectral index and tensor to scalar ratio r lie within the current WMAP 1-σ bounds. If the B−L symmetry breaking scale is of order a TeV or so, one of the three right handed neutrinos is a plausible cold dark matter candidate. Bounds on the dimensionless parameters λ, ξ and the gauge coupling gB−L are obtained.