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The Power Spectrum for a Multi-Component Inflaton to Second-Order Corrections in the Slow-Roll Expansion

Jin-Ook Gong·Ewan D. Stewart
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Abstract

We derive the power spectrum $\mathcal P(k)$ of the density perturbations produced during inflation up to second-order corrections in the standard slow-roll approximation for an inflaton with more than one degree of freedom. We also present the spectral index $n$ up to first-order corrections including previously missing terms, and the running ${dn}/{d\ln k}$ to leading order.

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Jin-Ook Gong, Ewan D. Stewart. 2002-02-05. The Power Spectrum for a Multi-Component Inflaton to Second-Order Corrections in the Slow-Roll Expansion. https://doi.org/10.1016/s0370-2693(02)02004-x

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