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arXiv · 1812.03667

Tensor Spectra Templates for Axion-Gauge Fields Dynamics during Inflation

Tomohiro Fujita·Evangelos I. Sfakianakis·Maresuke Shiraishi
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Abstract

$SU(2)$ gauge fields can generate large gravitational waves during inflation, if they are coupled to an axion which can be either the inflaton or a spectator field. The shape of the produced tensor power spectrum $\mathcal{P}_h$ depends on the form of the axion potential. We derive analytic expressions and provide general templates for $\mathcal{P}_h$ for various types of the spectator axion potential. Furthermore, we explore the detectability of the oscillatory feature, which is present in $\mathcal{P}_h$ in the case of an axion monodromy model, by possible future CMB B-mode polarization observations.

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Tomohiro Fujita, Evangelos I. Sfakianakis, Maresuke Shiraishi. 2018-12-10. Tensor Spectra Templates for Axion-Gauge Fields Dynamics during Inflation. https://doi.org/10.1088/1475-7516%2F2019%2F05%2F057

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