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arXiv · 1707.03023

Large Tensor Non-Gaussianity from Axion-Gauge Fields Dynamics

Aniket Agrawal·Tomohiro Fujita·Eiichiro Komatsu
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Abstract

We show that an inflation model in which a spectator axion field is coupled to an SU(2) gauge field produces a large three-point function (bispectrum) of primordial gravitational waves, $B_{h}$, on the scales relevant to the cosmic microwave background experiments. The amplitude of the bispectrum at the equilateral configuration is characterized by $B_{h}/P_h^2=\mathcal{O}(10)\times \Omega_A^{-1}$, where $\Omega_A$ is a fraction of the energy density in the gauge field and $P_h$ is the power spectrum of gravitational waves produced by the gauge field.

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Aniket Agrawal, Tomohiro Fujita, Eiichiro Komatsu. 2017-07-10. Large Tensor Non-Gaussianity from Axion-Gauge Fields Dynamics. https://doi.org/10.1103/physrevd.97.103526

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