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arXiv · 1007.5148

Scale-dependence of Non-Gaussianity in the Curvaton Model

Christian T. Byrnes·Kari Enqvist·Tomo Takahashi
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Abstract

We investigate the scale-dependence of f_NL in the self-interacting curvaton model. We show that the scale-dependence, encoded in the spectral index n_{f_NL}, can be observable by future cosmic microwave background observations, such as CMBpol, in a significant part of the parameter space of the model. We point out that together with information about the trispectrum g_NL, the self-interacting curvaton model parameters could be completely fixed by observations. We also discuss the scale-dependence of g_NL and its implications for the curvaton model, arguing that it could provide a complementary probe in cases where the theoretical value of n_{f_NL} is below observational sensitivity.

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Christian T. Byrnes, Kari Enqvist, Tomo Takahashi. 2010-07-29. Scale-dependence of Non-Gaussianity in the Curvaton Model. https://doi.org/10.1088/1475-7516/2010/09/026

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