Dark energy constraints from the thermal Sunyaev-Zeldovich power spectrum
Abstract
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 marginalizing 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 per cent precision, F = 0.460 ± 0.012 (68 per cent 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 per cent 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 model, the mass bias of B = 1.71 ± 0.17, i.e. 1 - b = 0.58 ± 0.06 (68 per cent CL).
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- July 2018
- DOI:
- 10.1093/mnras/sty823
- arXiv:
- arXiv:1712.00788
- Bibcode:
- 2018MNRAS.477.4957B
- Keywords:
-
- cosmological parameters;
- dark energy;
- cosmology: theory;
- cosmology: observations;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted version (MNRAS)