Probing a panoply of curvaton-decay scenarios using CMB data

TL;DR

This paper tests 27 curvaton-decay scenarios against CMB data to constrain the curvaton fraction and lepton asymmetry, providing predictions for non-Gaussian signatures for future observations.

Contribution

It systematically compares a wide range of curvaton-decay scenarios with CMB data, deriving constraints and predictions for non-Gaussianity.

Findings

Limits on the curvaton fraction at decay, $r_D$

Constraints on lepton asymmetry, $\xi_{ m lep}$

Predictions for non-Gaussian signatures

Abstract

In the curvaton scenario, primordial curvature perturbations are produced by a second field that is sub-dominant during inflation. Depending on how the curvaton decays [possibly producing baryon number, lepton number, or cold dark matter (CDM)], mixtures of correlated isocurvature perturbations are produced, allowing the curvaton scenario to be tested using cosmic microwave background (CMB) data. Here, a full range of 27 curvaton-decay scenarios is compared with CMB data, placing limits on the curvaton fraction at decay, $r_D$, and the lepton asymmetry, $\xi_{\rm lep}$. If baryon number is generated by curvaton decay and CDM before (or vice-versa), these limits imply specific predictions for non-Gaussian signatures testable by future CMB experiments and upcoming large-scale-structure surveys.