Tensor non-Gaussianity from axion-gauge-fields dynamics: parameter search

@article{Agrawal2018TensorNF,
  title={Tensor non-Gaussianity from axion-gauge-fields dynamics: parameter search},
  author={Aniket Agrawal and Tomohiro Fujita and Eiichiro Komatsu},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2018},
  volume={2018},
  pages={027 - 027}
}
We calculate the bispectrum of scale-invariant tensor modes sourced by spectator SU(2) gauge fields during inflation in a model containing a scalar inflaton, a pseudoscalar axion and SU(2) gauge fields. A large bispectrum is generated in this model at tree-level as the gauge fields contain a tensor degree of freedom, and its production is dominated by self-coupling of the gauge fields. This is a unique feature of non-Abelian gauge theory. The shape of the tensor bispectrum is approximately an… 
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54 Citations
Background Citations
20
Methods Citations
2
Results Citations
1

54 Citations

Parity Violating Non-Gaussianity from Axion-Gauge Field Dynamics

We study scalar-tensor-tensor and tensor-scalar-scalar three point cross correlations generated by the dynamics of a transiently rolling spectator axion-U(1) gauge field model during inflation. In…

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Axion-gauge field dynamics with backreaction

Phenomenological success of inflation models with axion and SU(2) gauge fields relies crucially on control of backreaction from particle production. Most of the previous study only demanded the…

Charged vector inflation

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We investigate the viability of inflation with a spectator sector comprised of non-Abelian gauge fields coupled through a higher order operator. We dub this model “spectator Gauge-flation”. We study…

Nonlinear perturbations from axion-gauge fields dynamics during inflation

We study a variant of the Chromo-Natural Inflation (CNI) mechanism in which the inflaton interacts only gravitationally with the CNI fields. Integrating out all the non-dynamical scalar fields of the…

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