# Constant-roll inflation: confrontation with recent observational data

## TL;DR

This paper evaluates constant-roll inflation models against recent observational data, finding that viable models are similar to slow-roll models with potentials close to natural inflation.

## Contribution

It provides the first comprehensive confrontation of constant-roll inflation models with the latest cosmological observations.

## Key findings

- Viable constant-roll models are close to slow-roll models.
- Allowed parameter regions are identified.
- Inflaton potentials resemble natural inflation but with differences.

## Abstract

The previously proposed class of phenomenological inflationary models in which the assumption of inflaton slow-roll is replaced by the more general, constant-roll condition is compared with the most recent cosmological observational data, mainly the Planck ones. Models in this two-parametric class which remain viable appear to be close to the slow-roll ones, and their inflaton potentials are close to (but still different from) that of the natural inflation model. Permitted regions for the two model parameters are presented.