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arXiv · 1404.3467

Constraints on the extensions to the base $Λ$CDM model from BICEP2, Planck and WMAP

Cheng Cheng·Qing-Guo Huang·Wen Zhao
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Abstract

Recently Background Imaging of Cosmic Extragalactic Polarization (B2) discovered the relic gravitational waves at $7.0σ$ confidence level. However, the other cosmic microwave background (CMB) data, for example Planck data released in 2013 (P13), prefer a much smaller amplitude of the primordial gravitational waves spectrum if a power-law spectrum of adiabatic scalar perturbations is assumed in the six-parameter $Λ$CDM cosmology. In this paper, we explore whether the $w$CDM model and the running spectral index can relax the tension between B2 and other CMB data. In particular, we find that a positive running of running of spectral index is preferred at $1.7σ$ level from the combination of B2, P13 and WMAP Polarization data.

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Cheng Cheng, Qing-Guo Huang, Wen Zhao. 2014-05-02. Constraints on the extensions to the base $Λ$CDM model from BICEP2, Planck and WMAP. https://arxiv.org/abs/1404.3467

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