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arXiv · 2108.12123

Generalized local ansatz for scale-dependent primordial non-Gaussianities and future galaxy surveys

Daisuke Yamauchi·Shuichiro Yokoyama·Tomo Takahashi
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Abstract

We revisit a possible scale-dependence of local-type primordial non-Gaussianities induced by super-horizon evolution of scalar field perturbations. We develop the formulation based on $δN$ formalism and derive the generalized form of the local-type bispectrum and also trispectrum which allows us to implement the scale-dependence and suitably compare model prediction with observational data. We propose simple but phenomenologically meaningful expressions, which encompass the information of a wide range of physically motivated models. We also formulate large-scale power spectrum and bispectrum of biased objects in the presence of the scale-dependent primordial non-Gaussianities. We perform the Fisher analysis for future galaxy surveys and give the projected constraints on the parameters of the generalized local-form of primordial non-Gaussianities.

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Daisuke Yamauchi, Shuichiro Yokoyama, Tomo Takahashi. 2021-10-13. Generalized local ansatz for scale-dependent primordial non-Gaussianities and future galaxy surveys. https://doi.org/10.1093/pasj%2Fpsab108

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