Perturbation, non-Gaussianity, and reheating in a Gauss-Bonnet <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>α</mml:mi></mml:math>-attractor model

Abstract

Motivated by $\ensuremath{\alpha}$-attractor models, in this paper we consider a Gauss-Bonnet inflation with an E-model-type of potential. We consider the Gauss-Bonnet coupling function to be the same as the E-model potential. In the small $\ensuremath{\alpha}$ limit, we obtain an attractor at $r=0$ as expected, and in the large $\ensuremath{\alpha}$ limit, we recover the Gauss-Bonnet model with potential and coupling function of the form ${\ensuremath{\phi}}^{2n}$. We study perturbations and non-Gaussianity in this setup, and we find some constraints on the model's parameters in comparison with PLANCK data sets. We study also the reheating epoch after inflation in this setup. For this purpose, we seek the number of e-folds and temperature during reheating epoch. These quantities depend on the model's parameter and the effective equation of state of the dominating energy density in the reheating era. We find some observational constraints on these parameters.