In the present work, we study a warm inflationary model defined by a quasi-exponential inflaton potential and an inflaton decay rate proportional to the Hubble rate. The model is characterized by three free parameters. We compute the power spectrum, the scalar spectral index, as well as the tensor-to-scalar ratio within the framework of the model, and we compare with the latest Planck data and also the BICEP2/Keck-Array data. On the $r-n_s$ plane, we show both the theoretical curves and the contour plots allowed by observations, and we constrain the parameters of the model accordingly. The nonlinear parameter $f_{NL}$, corresponding to primordial non-Gaussianities, is also discussed and we found that the value predicted by our model is within the bounds imposed by current observational data.

• Received 31 March 2018

DOI:https://doi.org/10.1103/PhysRevD.97.123503