CMB and reheating constraints to \alpha-attractor inflationary models

TL;DR

This paper analyzes -attractor inflationary models, deriving their predictions for spectral index and tensor-to-scalar ratio, and constrains their parameters using recent CMB and reheating data.

Contribution

It provides analytical and numerical predictions for -attractors and constrains their parameters based on recent observational data, including reheating effects.

Findings

Constraints on  parameter from CMB data

Reheating temperature and e-folds calculated as functions of spectral index

Range of  consistent with observational data identified

Abstract

After Planck 2013, a broad class of inflationary models called \alpha-attractors was developed which has universal observational predictions. For small values of the parameter \alpha, the models have good consistency with the recent CMB data. In this work, we first calculate analytically (and verify numerically) the predictions of these models for spectral index, n_s and tensor-to-scalar ratio, r and then using BICEP2/Keck 2015 data we impose constraints on \alpha-attractors. Then, we study the reheating in \alpha-attractors. The reheating temperature, T_{re} and the number of e-folds during reheating, N_{re} are calculated as functions of n_s. Using these results, we determine the range of free parameter \alpha for two clasees of \alpha-attractors which satisfy the constraints of recent CMB data.