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arXiv · 2206.11005

First measurement of projected phase correlations and large-scale structure constraints

Abstract

Phase correlations are an efficient way to extract astrophysical information that is largely independent from the power spectrum. We develop an estimator for the line correlation function (LCF) of projected fields, given by the correlation between the harmonic-space phases at three equidistant points on a great circle. We make a first, 6.5$σ$ measurement of phase correlations on data from the 2MPZ survey. Finally, we show that the LCF can significantly improve constraints on parameters describing the galaxy-halo connection that are typically degenerate using only two-point data.

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Felipe Oliveira Franco, Boryana Hadzhiyska, David Alonso. 2022-06-22. First measurement of projected phase correlations and large-scale structure constraints. https://arxiv.org/abs/2206.11005

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