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arXiv · 1511.07431

Probing a panoply of curvaton-decay scenarios using CMB data

Tristan L. Smith·Daniel Grin
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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, $ξ_{\rm lep}$. 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.

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Tristan L. Smith, Daniel Grin. 2015-11-23. Probing a panoply of curvaton-decay scenarios using CMB data. https://doi.org/10.1103/physrevd.94.103517

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