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arXiv · 2007.10763

Observational constraints on $α$-attractor inflationary models with a Higgs-like potential

J. G. Rodrigues·S. Santos da Costa·J. S. Alcaniz
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Abstract

We investigate the observational viability of a class of $α$-attractors inflationary models in light of the most recent Cosmic Microwave Background (CMB) and Large-Scale Structure (LSS) data. By considering a double-well potential we perform a slow-roll analysis to study the behavior of this class of models, which is a continuous interpolation between the chaotic inflation for large values of $α$ and the universal attractor, i.e., $n_s=1- 2/N$ and $r=α12/N^2$ for small $α$, where $n_s$ is the scalar spectral index, $r$ is the tensor-to-scalar ratio, and $N$ is the e-fold number. In order to explore the parameter space of the model, we also perform a MCMC analysis and find $α=7.56\pm 5.15$ ($1σ$).

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J. G. Rodrigues, S. Santos da Costa, J. S. Alcaniz. 2021-03-03. Observational constraints on $α$-attractor inflationary models with a Higgs-like potential. https://doi.org/10.1016/j.physletb.2021.136156

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