Testing an Inflation Model with Nonminimal Derivative Coupling in the
  Light of PLANCK 2015 Data
  We study the dynamics of a generalized inflationary model in which both the
scalar field and its derivatives are coupled to the gravity. We consider a
general form of the nonminimal derivative coupling in order to have a complete
treatment of the model. By expanding the action up to the second order in
perturbation, we study the spectrum of the primordial modes of the
perturbations. Also, by expanding the action up to the third order and
considering the three point correlation functions, the amplitude of the
non-Gaussianity of the primordial perturbations is studied both in equilateral
and orthogonal configurations. Finally, by adopting some sort of potentials, we
compare the model at hand with the Planck 2015 released observational data and
obtain some constraints on the model's parameters space. As an important
result, we show that the nonminimal couplings help to make models of chaotic
inflation, that would otherwise be in tension with Planck data, in better
agreement with the data. This model is consistent with observation at weak
coupling limit.
