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arXiv · 2011.13888

Viable Curvaton Models from the $f_{NL}$ Parameter

L. F. Guimarães·F. T. Falciano
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Abstract

We show how to build a curvaton inflationary model motivated by scale-dependent non-Gaussianities of cosmological perturbations. In particular, we study the change of sign in the $f_{NL}$ parameter as a function of the curvaton field value at horizon crossing and identify it with the cosmic microwave background pivot scale. We devise a procedure to recover the curvaton model that provides the desired $f_{NL}$ parameter. We then present a concrete example of $f_{NL}$ and construct its parent model. We study the constraints applied to this model based on considerations taken on $f_{NL}$. We show that the hemispherical asymmetry can also be used to constrain the scale-dependence of $f_{NL}$ and the model parameters.

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L. F. Guimarães, F. T. Falciano. 2020-11-27. Viable Curvaton Models from the $f_{NL}$ Parameter. https://doi.org/10.1103/physrevd.103.063530

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