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arXiv · 0909.3224

Detectability of the effect of Inflationary non-Gaussianity on halo bias

Licia Verde·Sabino Matarrese
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Abstract

We consider the description of the clustering of halos for physically-motivated types of non-Gaussian initial conditions. In particular we include non-Gaussianity of the type arising from single field slow-roll, multi fields, curvaton (local type), higher-order derivative-type (equilateral), vacuum-state modifications (enfolded-type) and horizon-scale GR corrections type. We show that large-scale halo bias is a very sensitive tool to probe non-Gaussianity, potentially leading, for some planned surveys, to a detection of non-Gaussianity arising from horizon-scale GR corrections. In tandem with cosmic microwave background constraints, the halo-bias approach can help enormously to discriminate among different shapes of non-Gaussianity and thus among models for the origin of cosmological perturbations.

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Licia Verde, Sabino Matarrese. 2009-09-17. Detectability of the effect of Inflationary non-Gaussianity on halo bias. https://doi.org/10.1088/0004-637x/706/1/l91

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