Accuracy of cosmological parameters-JCAP-1501-2015-Accepted.pdf (2.39 MB)
Accuracy of cosmological parameters using the baryon acoustic scale
journal contribution
posted on 2023-06-08, 22:53 authored by Kiattisak Thepsuriya, Antony LewisAntony LewisPercent-level measurements of the comoving baryon acoustic scale standard ruler can be used to break degeneracies in parameter constraints from the CMB alone. The sound horizon at the epoch of baryon drag is often used as a proxy for the scale of the peak in the matter density correlation function, and can conveniently be calculated quickly for different cosmological models. However, the measurements are not directly constraining this scale, but rather a measurement of the full correlation function, which depends on the detailed evolution through decoupling. We assess the level of reliability of parameter constraints based on a simple approximation of the acoustic scale compared to a more direct determination from the full numerical two-point correlation function. Using a five-parameter fitting technique similar to recent BAO data analyses, we find that for standard _CDM models and extensions with massive neutrinos and additional relativistic degrees of freedom, the approximation is at better than 0:15% for most parameter combinations varying over reasonable ranges.
Funding
ERC
STFC
History
Publication status
- Published
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- Accepted version
Journal
Journal of Cosmology and Astroparticle PhysicsISSN
1475-7516Publisher
IOP PublishingExternal DOI
Issue
01Volume
2015Page range
034-034Department affiliated with
- Physics and Astronomy Publications
Full text available
- Yes
Peer reviewed?
- Yes
Legacy Posted Date
2015-10-22First Open Access (FOA) Date
2015-10-22First Compliant Deposit (FCD) Date
2015-10-21Usage metrics
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