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

Abstract

We investigate the observational viability of a class of $\alpha$-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 $\alpha$ and the universal attractor, i.e., $n_s=1-2/N$ and $r=\alpha 12/N^2$ for small $\alpha$, 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 $\alpha =7.56\pm 5.15$ ($1\sigma$).

Comments: 22 pages, 6 figures, 2 tables. Minor corrections and references added. Version accepted for publication in Physics Letters B