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arXiv · 1303.3499

Angular Correlation Functions for Models with Logarithmic Oscillations

Mark G. Jackson·Ben Wandelt·François Bouchet
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Abstract

There exist several theoretical motivations for primordial correlation functions (such as the power spectrum) to contain oscillations as a logarithmic function of comoving momentum k. While these features are commonly searched for in k-space, an alternative is to use angular space; that is, search for correlations between the directional vectors of observation. We develop tools to efficiently compute the angular correlations based on a stationary phase approximation and examine several example oscillations in the primordial power spectrum, bispectrum, and trispectrum. We find that logarithmically-periodic oscillations are essentially featureless and therefore difficult to detect using the standard correlator, though others might be feasible.

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Mark G. Jackson, Ben Wandelt, François Bouchet. 2013-03-14. Angular Correlation Functions for Models with Logarithmic Oscillations. https://doi.org/10.1103/physrevd.89.023510

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