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arXiv · 1502.06506

Gauge-preheating and the end of axion inflation

Peter Adshead·John T. Giblin Jr·Timothy R. Scully·Evangelos I. Sfakianakis
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Abstract

We study the onset of the reheating epoch at the end of axion-driven inflation where the axion is coupled to an Abelian, $U(1)$, gauge field via a Chern-Simons interaction term. We focus primarily on $m^2ϕ^2$ inflation and explore the possibility that preheating can occur for a range of coupling values consistent with recent observations and bounds on the overproduction of primordial black holes. We find that for a wide range of parameters preheating is efficient. In certain cases the inflaton is seen to transfer all its energy to the gauge fields within a few oscillations. In most cases, we find that the gauge fields on sub-horizon scales end preheating in an unpolarized state due to the existence of strong rescattering between the inflaton and gauge-field modes. We also present a preliminary study of an axion monodromy model coupled to $U(1)$ gauge fields, seeing a similarly efficient preheating behavior as well as indications that the coupling strength has an effect on the creation of oscillons.

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Peter Adshead, John T. Giblin Jr, Timothy R. Scully, Evangelos I. Sfakianakis. 2016-12-23. Gauge-preheating and the end of axion inflation. https://doi.org/10.1088/1475-7516%2F2015%2F12%2F034

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