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arXiv · 1207.7006

Curvaton and the inhomogeneous end of inflation

Hooshyar Assadullahi·Hassan Firouzjahi·Mohammad Hossein Namjoo·David Wands
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Abstract

We study the primordial density perturbations and non-Gaussianities generated from the combined effects of an inhomogeneous end of inflation and curvaton decay in hybrid inflation. This dual role is played by a single isocurvature field which is massless during inflation but acquire a mass at the end of inflation via the waterfall phase transition. We calculate the resulting primordial non-Gaussianity characterized by the non-linearity parameter, $f_{NL}$, recovering the usual end-of-inflation result when the field decays promptly and the usual curvaton result if the field decays sufficiently late.

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Hooshyar Assadullahi, Hassan Firouzjahi, Mohammad Hossein Namjoo, David Wands. 2012-07-30. Curvaton and the inhomogeneous end of inflation. https://doi.org/10.1088/1475-7516%2F2012%2F12%2F024

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