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arXiv · 1012.1372

Observable Signatures of Inflaton Decays

Diana Battefeld·Thorsten Battefeld·John T. Giblin Jr.·Evan K. Pease
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Abstract

We numerically compute features in the power-spectrum that originate from the decay of fields during inflation. Using a simple, phenomenological, multi-field setup, we increase the number of fields from a few to thousands. Whenever a field decays, its associated potential energy is transferred into radiation, causing a jump in the equation of state parameter and mode mixing at the perturbed level. We observe discrete steps in the power-spectrum if the number of fields is low, in agreement with analytic arguments in the literature. These features become increasingly smeared out once many fields decay within a given Hubble time. In this regime we confirm the validity of the analytic approach to staggered inflation, which is based on a coarse-graining procedure. Our numerical approach bridges the aforementioned analytic treatments, and can be used in more complicated scenarios.

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Diana Battefeld, Thorsten Battefeld, John T. Giblin Jr., Evan K. Pease. 2010-12-07. Observable Signatures of Inflaton Decays. https://doi.org/10.1088/1475-7516/2011/02/024

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