Particle production during inflation: A Bayesian analysis with CMB data
  from Planck 2018
  A class of inflationary models that involve rapid bursts of particle
productions predict observational signatures, such as bump-like features in the
primordial scalar power spectrum. In this work, we analyze such models by
comparing their predictions with the latest CMB data from Planck 2018. We
consider two scenarios of particle production. The first one is a simple
scenario consisting of a single burst of particle production during observable
inflation. The second one consists of multiple bursts of particle production
that lead to a series of bump-like features in the primordial power spectrum.
We find that the second scenario of the multi-bump model gives better fit to
the CMB data compared to the concordance $\Lambda$CDM model. We carried out
model comparisons using Bayesian evidences. From the observational constraints
on the amplitude of primordial features of the multi-bump model, we find that
the coupling parameter $g$ responsible for particle production is bound to be
$g< 0.05$.
