Non-Gaussianity from Particle Production during Inflation

Figure 7

A comparison of curvature fluctuations from different physical effects. The dashed blue line is the usual (nearly) scale invariant vacuum fluctuations from inflation. The red solid line is the bump-like feature induced by rescattering and IR cascading. The dotted blue line is the ringing pattern resulting from the momentary slowing-down of the inflaton (computed using the mean field approach of [64]). The vertical lines show 𝑎𝐻 at the beginning of particle production and after ~3𝑒-foldings. This figure clearly illustrates the dominance of IR cascading over backreaction effects. For illustration we have taken 𝑔²=0.1, but the dominance is generic for all values of the coupling.