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arXiv · 1202.0553

The Effects of Primordial Non-Gaussianity on Giant-Arc Statistics: A Scale Dependent Example

Anson D'Aloisio·Priyamvada Natarajan
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Abstract

In a recently published article, we quantified the impact of primordial non-Gaussianity on the probability of giant-arc formation. In that work, we focused on the local form of non-Gaussianity and found that it can have only a modest effect given the most recent constraints from Cosmic Microwave Background (CMB) measurements. Here, we present new calculations using a parameterization of scale-dependent non-Gaussianity in which the primordial bispectrum has the equilateral shape and the effective f_NL parameter depends on scale. We find that non-Gaussianity of this type can yield a larger effect on the giant-arc abundance compared to the local form due to both the scale dependence and the relatively weaker constraints on the equilateral shape from CMB measurements. In contrast to the maximum ~40% effect (within the latest CMB constraints) previously found for the local form, we find that the predicted giant-arc abundance for the scale-dependent equilateral form can differ by a factor of a few with respect to the Gaussian case.

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Anson D'Aloisio, Priyamvada Natarajan. 2012-02-02. The Effects of Primordial Non-Gaussianity on Giant-Arc Statistics: A Scale Dependent Example. https://arxiv.org/abs/1202.0553

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