Constant-roll tachyon inflation and observational constraints

TL;DR

This paper derives analytical expressions for perturbation spectra in constant-roll tachyon inflation, compares predictions with observations, and finds that observational data favor slow-roll inflation, constraining the model.

Contribution

It provides the first analytical derivation of scalar and tensor spectra in constant-roll tachyon inflation and compares these with observational constraints.

Findings

Only one constant-roll inflation model matches observations.

Observations favor slow-roll inflation over constant-roll in this context.

The tachyon potential consistent with observations is reconstructed.

Abstract

For the constant-roll tachyon inflation, we derive the analytical expressions for the scalar and tensor power spectra, the scalar and tensor spectral tilts and the tensor to scalar ratio up to the first order by using the method of Bessel function approximation. The derived $n_s-r$ results for the constant-roll inflation are also compared with the observations, we find that only one constant-roll inflation is consistent with the observations and observations constrain the constant-roll inflation to be slow-roll inflation. The tachyon potential is also reconstructed for the constant-roll inflation which is consistent with the observations.