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arXiv · 1004.0461

Quadra-Spectrum and Quint-Spectrum from Inflation and Curvaton Models

Chunshan Lin·Yi Wang
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Abstract

We calculate the quadra-spectrum and quint-spectrum, corresponding to five and six point correlation functions of the curvature perturbation. For single field inflation with standard kinetic term, the quadra-spectrum and quint-spectrum are small, which are suppressed by slow roll parameters. The calculation can be generalized to multiple fields. When there is no entropy perturbation, the quadra-spectrum and quint-spectrum are suppressed as well. With the presence of entropy perturbation, the quadra-spectrum and quint-spectrum can get boosted. We illustrate this boost in the multi-brid inflation model. For the curvaton scenario, the quadra-spectrum and quint-spectrum are also large in the small r limit. We also calculate representative terms of quadra-spectrum and quint-spectrum for inflation with generalized kinetic terms, and estimate their order of magnitude for quasi-single field inflation.

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Chunshan Lin, Yi Wang. 2010-04-03. Quadra-Spectrum and Quint-Spectrum from Inflation and Curvaton Models. https://doi.org/10.1088/1475-7516/2010/07/011

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