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arXiv · 1309.6624

Reconstructing primordial power spectrum using Planck and SDSS-III measurements

Xin Wang·Gong-Bo Zhao
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Abstract

We develop an accurate and efficient Bayesian method to reconstruct the primordial power spectrum in a model-independent way, and apply it to the latest cosmic microwave background measurement from Planck mission, and the large scale structure observation of SDSS-III BOSS (CMASS) sample, combined with the type Ia supernovae sample (SNLS 3-year) and the measurements of baryon acoustic oscillations from SDSS-II, 6dF, and WiggleZ survey. We confirm that the scale-invariant primordial power spectrum is strongly disfavored, and a model with suppressed power on horizon scales is supported by current data. We also find that a modulation on scales $5\times10^{-4}~\textrm{Mpc}^{-1} \lesssim k \lesssim 0.01~\textrm{Mpc}^{-1}$ is mildly preferred at $2σ$ confidence level, whose origin needs further investigation.

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Xin Wang, Gong-Bo Zhao. 2014-01-27. Reconstructing primordial power spectrum using Planck and SDSS-III measurements. https://arxiv.org/abs/1309.6624

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