We constrain the dark energy equation of state parameter, w, using the power spectrum of the thermal Sunyaev-Zeldovich (tSZ) effect. We improve upon previous analyses by taking into account the trispectrum in the covariance matrix and marginalising over the foreground parameters, the correlated noise, the mass bias B in the Planck universal pressure profile, and all the relevant cosmological parameters (i.e., not just Ωm and σ8). We find that the amplitude of the tSZ power spectrum at ℓ≲103 depends primarily on F≡σ8(Ωm/B)0.40h−0.21, where B is related to more commonly used variable b by B=(1−b)−1. We measure this parameter with 2.6\% precision, F=0.460±0.012 (68% CL). By fixing the bias to B=1.25 and adding the local determination of the Hubble constant H0 and the amplitude of the primordial power spectrum constrained by the Planck Cosmic Microwave Background (CMB) data, we find w=−1.10±0.12, σ8=0.802±0.037, and Ωm=0.265±0.022 (68% CL). Our limit on w is consistent with and is as tight as that from the distance-alone constraint from the CMB and H0. Finally, by combining the tSZ power spectrum and the CMB data we find, in the Λ Cold Dark Matter (CDM) model, the mass bias of B=1.71±0.17, i.e., 1−b=0.58±0.06 (68% CL).
@article{arxiv.1712.00788,
title = {Dark Energy from the Thermal Sunyaev Zeldovich Power Spectrum},
author = {Boris Bolliet and Barbara Comis and Eiichiro Komatsu and Juan Francisco Macías-Pérez},
journal= {arXiv preprint arXiv:1712.00788},
year = {2018}
}