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arXiv · 1802.09185

$α$-Attractor and Reheating in a Model with Non-Canonical Scalar Fields

Narges Rashidi·Kourosh Nozari
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Abstract

We consider two non-canonical scalar fields (tachyon and DBI) with E-model type of the potential. We study cosmological inflation in these models to find possible $α$-attractors. We show that similar to the canonical scalar field case, in both tachyon and DBI models there is a value of the scalar spectral index in small $α$ limit which is just a function of the e-folds number. However, the value of $n_{s}$ in DBI model is somewhat different from the other ones. We also compare the results with Planck2015 TT, TE, EE+lowP data. The reheating phase after inflation is studied in these models which gives some more constraints on the model's parameters.

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Narges Rashidi, Kourosh Nozari. 2018-02-26. $α$-Attractor and Reheating in a Model with Non-Canonical Scalar Fields. https://doi.org/10.1142/s0218271818500761

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