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

  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},
  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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