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The WiggleZ Dark Energy Survey: probing the epoch of radiation domination using large-scale structure

Poole, Gregory B.; Blake, Chris; Parkinson, David; Brough, Sarah; Colless, Matthew; Contreras, Carlos; Couch, Warrick; Croton, Darren J.; Croom, Scott; Davis, Tamara; Drinkwater, Michael J.; Forster, Karl; Gilbank, David; Gladders, Mike; Glazebrook, Karl; Jelliffe, Ben; Jurek, Russell J.; Li, I-hui; Madore, Barry; Martin, D. Christopher; Pimbblet, Kevin; Pracy, Michael; Sharp, Rob; Wisnioski, Emily; Woods, David; Wyder, Ted K.; Yee, H. K. C.


Gregory B. Poole

Chris Blake

David Parkinson

Sarah Brough

Matthew Colless

Carlos Contreras

Warrick Couch

Darren J. Croton

Scott Croom

Tamara Davis

Michael J. Drinkwater

Karl Forster

David Gilbank

Mike Gladders

Karl Glazebrook

Ben Jelliffe

Russell J. Jurek

I-hui Li

Barry Madore

D. Christopher Martin

Michael Pracy

Rob Sharp

Emily Wisnioski

David Woods

Ted K. Wyder

H. K. C. Yee


We place the most robust constraint to date on the scale of the turnover in the cosmological matter power spectrum using data from the WiggleZ Dark Energy Survey. We find this feature to lie at a scale of k 0 = 0.0160 +0.0035 -0.0041 (h Mpc -1 ) (68 per cent confidence) for an effective redshift of z eff = 0.62 and obtain from this the first ever turnover-derived distance and cosmology constraints: a measure of the cosmic distance-redshift relation in units of the horizon scale at the redshift of radiation-matter equality (r H ) ofDV(z eff = 0.62)/r H = 18.3 +6.3 -3.3 and, assuming a prior on the number of extra relativistic degrees of freedom N eff =3, constraints on the cosmological matter density parameter Ω M h 2 = 0.136 +0.026 -0.052 and on the redshift of matter-radiation equality z eq = 3274 +631 -1260 .We stress that these results are obtained within the theoretical framework of Gaussian primordial fluctuations and linear large-scale bias. With this caveat, all results are in excellent agreement with the predictions of standard ΛCDM models. Our constraints on the logarithmic slope of the power spectrum on scales larger than the turnover are bounded in the lower limit with values only as low as -1 allowed, with the prediction of P(k) ∝ k from standard ΛCDM models easily accommodated by our results. Finally, we generate forecasts to estimate the achievable precision of future surveys at constraining k 0 , ω; M h 2 , z eq and N eff .We find that the Baryon Oscillation Spectroscopic Survey should substantially improve upon the WiggleZ turnover constraint, reaching a precision on k0 of ±9 per cent (68 per cent confidence), translating to precisions on ω M h 2 and z eq of±10 per cent (assuming a prior N eff =3) and onNeff of +78 -56 per cent (assuming a priorω M h 2 = 0.135). This represents sufficient precision to sharpen the constraints on N eff from WMAP, particularly in its upper limit. For Euclid, we find corresponding attainable precisions on (k 0 , ω M h 2 , N eff ) of (3, 4, +17 -21 ) per cent. This represents a precision approaching our forecasts for the Planck Surveyor. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Journal Article Type Article
Publication Date Mar 1, 2013
Journal Monthly notices of the Royal Astronomical Society
Print ISSN 0035-8711
Electronic ISSN 0035-8711
Publisher Oxford University Press (OUP)
Peer Reviewed Peer Reviewed
Volume 429
Issue 3
Pages 1902-1912
APA6 Citation Poole, G. B., Blake, C., Parkinson, D., Brough, S., Colless, M., Contreras, C., …Yee, H. K. C. (2013). The WiggleZ Dark Energy Survey: probing the epoch of radiation domination using large-scale structure. Monthly notices, containing papers, abstracts of papers, and reports of the proceedings of the Society, 429(3), 1902-1912.
Keywords Surveys; Cosmological parameters; Large-scale structure of Universe
Publisher URL


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Copyright Statement
© 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society

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