# 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…

## 54 Citations

### Parity Violating Non-Gaussianity from Axion-Gauge Field Dynamics

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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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Several models of inflation employing a triplet of SU(2) vectors with spatially orthogonal vacuum expectation values (VEVs) have been recently proposed. One (tensor) combination t of the vector modes…

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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…

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We present a model of inflation in which the inflaton field is charged under a triplet of $U(1)$ gauge fields. The model enjoys an internal $O(3)$ symmetry supporting the isotropic FRW solution. With…

### Gravitational Waves from a Rolling Axion Monodromy

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### Nonlinear perturbations from axion-gauge fields dynamics during inflation

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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…

### Tensor non-gaussianities from non-minimal coupling to the inflaton

- PhysicsJournal of Cosmology and Astroparticle Physics
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Tensor non-Gaussianity represents an important future probe of the physics of inflation. Inspired by recent works, we elaborate further on the possibility of significant primordial tensor…

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