Inflation Story: slow-roll and beyond
  We present constraints on inflationary dynamics and features in the
primordial power spectrum of scalar perturbations using the Cosmic Microwave
Background temperature, polarization data from Planck 2018 data release and
updated likelihoods. We constrain the slow-roll dynamics using Hilltop Quartic
Potential and Starobinsky $R+R^2$ model in the Einstein frame using the Planck
2018 binned Plik likelihood. Using the Hilltop as base potential we construct
Whipped Inflation potential to introduce suppression in the scalar power
spectrum at large angular scales. We notice marginal (68% C.L.) preference of
suppression from the large scale temperature angular power spectrum. However,
large-scale E-mode likelihood, based on high frequency instrument cross
spectrum, does not support this suppression and in the combined data the
preference towards the suppression becomes negligible. Based on the Hilltop and
Starobinsky model we construct the Wiggly Whipped Inflation potentials to
introduce oscillatory features along with the suppression. We use unbinned data
from the recently released CamSpec v12.5 likelihood which updates Planck 2018
results. We compare the Bayesian evidences of the feature models with their
baseline slow-roll potentials. We find that the complete slow-roll baseline
potential is moderately preferred against potentials which generate features.
Compared to Planck 2015 PlikHM bin1 likelihood, we find that the significance
of sharp features has decreased owing to the updates in the data analysis
pipeline. We also compute the bispectra for the best fit candidates obtained
from our analysis.
