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arXiv · 1404.0951

Curvaton in large field inflation

Tomohiro Fujita·Masahiro Kawasaki·Shuichiro Yokoyama
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Abstract

We comprehensively explore the quadratic curvaton models in the chaotic inflation. In the light of the BICEP2 result $r \approx 0.2$, all model parameters and relevant observables are computed. It is found the curvaton field value is constrained into a narrow range, $σ_* = \mathcal{O}(10^{-2}$-$10^{-1})$ and the running of the spectral index is $n_s' \gtrsim -10^{-3}$. We show that if the curvaton is added, the models are heavily degenerated on the $n_s$ - $r$ plane. However, introducing a new plane, the degeneracy can be resolved. To distinguish the curvaton models, precise measurements of not only $r$ but also $n_s'$ and the tensor tilt $n_T$ are required.

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Tomohiro Fujita, Masahiro Kawasaki, Shuichiro Yokoyama. 2014-06-04. Curvaton in large field inflation. https://doi.org/10.1088/1475-7516%2F2014%2F09%2F015

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