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arXiv · 1108.2635

The WiggleZ Dark Energy Survey: mapping the distance-redshift relation with baryon acoustic oscillations

Abstract

We present measurements of the baryon acoustic peak at redshifts z = 0.44, 0.6 and 0.73 in the galaxy correlation function of the final dataset of the WiggleZ Dark Energy Survey. We combine our correlation function with lower-redshift measurements from the 6-degree Field Galaxy Survey and Sloan Digital Sky Survey, producing a stacked survey correlation function in which the statistical significance of the detection of the baryon acoustic peak is 4.9-sigma relative to a zero-baryon model with no peak. We fit cosmological models to this combined baryon acoustic oscillation (BAO) dataset comprising six distance-redshift data points, and compare the results to similar fits to the latest compilation of supernovae (SNe) and Cosmic Microwave Background (CMB) data. The BAO and SNe datasets produce consistent measurements of the equation-of-state w of dark energy, when separately combined with the CMB, providing a powerful check for systematic errors in either of these distance probes. Combining all datasets we determine w = -1.03 +/- 0.08 for a flat Universe, consistent with a cosmological constant model. Assuming dark energy is a cosmological constant and varying the spatial curvature, we find Omega_k = -0.004 +/- 0.006.

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BibTeXRIS

Chris Blake, Eyal Kazin, Florian Beutler, Tamara Davis, David Parkinson, Sarah Brough, Matthew Colless, Carlos Contreras, Warrick Couch, Scott Croom, Darren Croton, Michael J. Drinkwater, Karl Forster, David Gilbank, Mike Gladders, Karl Glazebrook, Ben Jelliffe, Russell J. Jurek, I-hui Li, Barry Madore, Chris Martin, Kevin Pimbblet, Gregory Poole, Michael Pracy, Rob Sharp, Emily Wisnioski, David Woods, Ted Wyder, Howard Yee. 2011-08-12. The WiggleZ Dark Energy Survey: mapping the distance-redshift relation with baryon acoustic oscillations. https://doi.org/10.1111/j.1365-2966.2011.19592.x

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