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arXiv · 1807.03596

Constraints on the generalized natural inflation after Planck 2018

Nan Zhang·Ya-Bo Wu·Jun-Wang Lu·Chu-Wen Sun·Li-Jie Shou·Hai-Zhou Xu
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Abstract

Based on the dynamics of single scalar field slow-roll inflation and the theory of reheating, we investigate the generalized natural inflationary (GNI) model. Concretely, we give constraints on the scalar spectral index $n_{s}$ and tensor-to scalar ratio $r$ for $\Lambda$CDM $+r$ model according to the latest data from Plack 2018 TT,TE,EE+lowE+lensing (P18) and BICEP2/Keck 2015 season (BK15), i.e., $n_{s}=0.9659\pm0.0044$ at $68\%$ confidence level (CL) and $r<0.0623$ at $95\%$CL. We find that the GNI model is favored by P18 plus BK15 in the ranges of $\log_{10}(f/M_{p})=0.62^{+0.17}_{-0.18}$ and $m=0.35^{+0.13}_{-0.23}$ at $68\%$CL. In addition, the corresponding predictions of the general and two-phase reheating are respectively discussed. It follows that the parameter $m$ has the significant effect on the model behaviors.

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Nan Zhang, Ya-Bo Wu, Jun-Wang Lu, Chu-Wen Sun, Li-Jie Shou, Hai-Zhou Xu. 2018-07-10. Constraints on the generalized natural inflation after Planck 2018. https://arxiv.org/abs/1807.03596

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