Study of Inflationary Observable with Generalized Galileon Coupling Function

The main goal of this article is to explore a model with inflation inspired by Galileon inflaton field and how this model is modified by introducing a generalized coupling form G(phi, X) = -phi X-2p+1(q)/M-6q, in the action. The analytical solutions of the inflaton field and corresponding potential are obtained under slow-roll approximation using specific evolution of the isotropic scale factor, i.e., intermediate, logamediate and exponential. Consistency of the predictions of the model with observations is being done by computing the scalar-tensor power spectra, the scalar spectral index, its running as well as the tensor-scalar ratio. For all the three models with inflation, we constrain the involved model parameters for which its predictions lie inside the allowed region from Planck 2015 data.