Confronting the Potential-driven DBI-inspired nonminimal kinetic coupling (Dinkic) inflation to the observational data

Abstract

In the previous work, a new kind of inflation model was proposed, which has the interesting property that its perturbation equation of motion gets a correction of k^4, due to the non-linearity of the kinetic term. Nonetheless, the scale-invariance of the power spectrum remains valid, both in large-k and small-k limits. In this paper, we investigate in detail the spectral index, the index running and the tensor/scalar ratio in this model, especially on the potential-driven case, and compare the results to the current PLANCK/BICEP observational data. We also discuss the tensor spectrum in this case, which is expected to be tested by the future observations on primordial gravitational waves.