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arXiv · 1309.4082

Particle Production during Inflation in Light of PLANCK

Diana Battefeld·Thorsten Battefeld·Daniel Fiene
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Abstract

We consider trapped inflation in a higher dimensional field space: particle production at a dense distribution of extra species points leads to a terminal velocity at which inflation can be driven in steep potentials. We compute an additional, nearly scale invariant contribution to the power-spectrum, caused by back-scattering of the continuously produced particles. Since this contribution has a blue tilt, it has to be sub-dominant, leading to an upper bound on the coupling constant between the inflatons and the extra species particles. The remaining allowed parameter space is narrow.

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Diana Battefeld, Thorsten Battefeld, Daniel Fiene. 2014-05-21. Particle Production during Inflation in Light of PLANCK. https://doi.org/10.1103/physrevd.89.123523

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