Constraining N=1 supergravity inflation with non-minimal Kahler operators using δN formalism

In this paper I provide a general framework based on delta N formalism to study the features of unavoidable higher dimensional non-renormalizable Kahler operators for N = 1 supergravity (SUGRA) during primordial inflation from the combined constraint on nonGaussianity, sound speed and CMB dipolar asymmetry as obtained from the recent Planck data. In particular I study the nonlinear evolution of cosmological perturbations on large scales which enables us to compute the curvature perturbation, zeta, without solving the exact perturbed field equations. Further I compute the non-Gaussian parameters f(NL), T-NL and g(NL) for local type of non-Gaussianities and CMB dipolar asymmetry parameter, A(CMB), using the delta N formalism for a generic class of sub-Planckian models induced by the Hubble-induced corrections for a minimal supersymmetric D-flat direction where inflation occurs at the point of inflection within the visible sector. Hence by using multi parameter scan I constrain the non-minimal couplings appearing in non-renormalizable Kahler operators within, O(1), for the speed of sound, 0.02 <= cs <= 1, and tensor to scalar, 10(-22) <= r(*) <= 0.12. Finally applying all of these constraints I will fix the lower as well as the upper bound of the non-Gaussian parameters within, O(1 -5) <= fNL <= 8.5, O(75 - 150) <= T-NL = 2800 and O(17.4 - 34.7) <= gNL <= 648.2, and CMB dipolar asymmetry parameter within the range, 0.05 <= ACMB <= 0.09.