The Location of CMB Peaks in a Universe with Dark Energy

Michael Doran; Matthew Lilley

doi:10.1046/j.1365-8711.2002.05144.x

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arXiv · astro-ph/0104486

The Location of CMB Peaks in a Universe with Dark Energy

Michael Doran·Matthew Lilley

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Abstract

The locations of the peaks of the CMB spectrum are sensitive indicators of cosmological parameters, yet there is no known analytic formula which accurately describes their dependence on them. We parametrize the location of the peaks as l_m = l_A(m - ϕ_m), where l_A is the analytically calculable acoustic scale and m labels the peak number. Fitting formulae for the phase shifts ϕ_m for the first three peaks and the first trough are given. It is shown that in a wide range of parameter space, the acoustic scale l_A can be retrieved from actual CMB measurements of the first three peaks within one percent accuracy. This can be used to speed up likelihood analysis. We describe how the peak shifts can be used to distinguish between different models of dark energy.

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Michael Doran, Matthew Lilley. 2002-05-21. The Location of CMB Peaks in a Universe with Dark Energy. https://doi.org/10.1046/j.1365-8711.2002.05144.x

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